Method and equipment for treating electrostatic field and electrode used therein

ABSTRACT

A method of treating a food object in an electrostatic field to thaw food rapidly at temperatures between 0° C. and a freezing temperature of an object to be treated. By applying the electrostatic field, the freezing temperature of the food is lowered but the food does not freeze in the electrostatic field. Accordingly, foods are kept fresher longer and the freshness can be maintained over a range of temperatures.

FIELD AND ELECTRODE USED THEREIN

[0001] 1. Technical Field

[0002] This invention relates to electrostatic treatment used forfreezing, and freshness keeping of food and oxidation inhibition ofedible oil.

[0003] 2. Technical Background

[0004] Conventionaly, meat and fish were thawed in the range of minustemperature in a refrigerator. Further, fruit as well as meat and fishwas kept fresh therein, and these technics are disclosed in JapanesePatent Publication Hei5-77387. In this method, the whole part of arefrigerator is completely insulated from its floor and a voltage of5,000 V to 20,000 V is impressed on the shelves of the refrigerator by anegative electron generating apparatus through the inner wall of therefrigerator to thaw food in a low temperature range of −3° C. to +3° C.Further, in the negative electron generating apparatus, one pole of thesecondary side of a transformer is completely closed and insulated, anda high output resistance is provided on the other pole.

[0005] In these method and apparatus, since one pole of the electrongenerating apparatus is insulated, a large output is required on thesecondary side of the transformer. Further, since the whole part of therefrigerator is insulated from the floor, and the casing of therefrigerator is not ground, the casing of the refrigerator is chargedwith electricity, and an operator sometimes receives an electric shockto cause a danger of a secondary accident. In addition, there was aconventional fryer in which oil in an oil tank is charged withelectricity to prevent oxidation of the oil. Such a fryer is disclosedin Japanese Patent Publication Hei7-78298, that is, an electrode is setin the oil tank with a high voltage electrostatic transformer or avoltage is directly impressed on the oil tank itself thereby. In thiscase, the whole part of the fryer is insulated from the floor, one poleon the secondary high voltage side of the high voltage electrostatictransformer is insulated and the other pole is connected to an electrodeor the oil tank. However, unless the transformer having one pole thereofinsulated and closed is adjusted so that a large output is generated onthe secondary side thereof, a necessary voltage cannot be impressed onthe oil itself. Further, since the whole of the fryer is insulated fromthe floor, the casing of the fryer is charged with electricity to causean electric shock of an operator.

[0006] Therefore, it is an object of this invention to provide anelectrostatic treatment method and apparatus which are safe andeffective even if the secondary side output voltage of the transformeris relatively small.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007]FIG. 1 shows a schematic structural view of a refrigerator of thisinvention.

[0008]FIG. 2 shows an electric circuit view of a high voltage generatingdevice.

[0009]FIG. 3 is a graph showing the relationship between voltage andtemperature in method of keeping freshness of vegetables.

[0010]FIG. 4 is a graph showing the relationship between voltage andtemperature in method of thawing meat.

[0011]FIG. 5 is a graph showing the relationship between voltage andtemperature in method of thawing fishes and shellfishes.

[0012]FIG. 6 is a graph showing the relationship between voltage andtemperature in method of maintaining freshness of fishes andshellfishes.

[0013]FIG. 7 is a graph showing the relationship between impressedvoltage and freezing temperature of fruits, vegetables, fishes and meat.

[0014]FIG. 8 shows a perspective view of an electrode plate.

[0015]FIG. 9 shows a cross sectional view of the electrode plate.

[0016]FIG. 10 is a perspective view of a connecting member forconnecting the high voltage generating device to the shelf of arefrigerator.

[0017]FIG. 11 is a schematic view of a refrigerator of this invention.

[0018]FIG. 12 is a sectional view showing a setting state of anelectrode.

[0019]FIG. 13 is a sectional view showing a setting state of anelectrode.

[0020]FIG. 14 is a sectional view showing a setting state of anelectrode.

[0021]FIG. 15 is a perspective view of an insulating electrode.

[0022]FIG. 16 shows a cross sectional view of the end portion of theinsulating electrode.

[0023]FIG. 17 shows a perspective view of an electrode unit set in arefrigerator.

[0024]FIG. 18 is an explanatory view showing a state of joining anelectrode plate with a slit portion.

[0025]FIG. 19 is a perspective view of the slit portion for receivingthe electrode plate in the electrode unit.

[0026]FIG. 20 is a perspective view showing a state in which a voltageis impressed indirectly on the electrode plate.

[0027]FIG. 21 is a sectional view taken along a line XXI-XXI in FIG. 20.

[0028]FIG. 22 is an explanatory view showing a state in which animpressed voltage is changeable.

[0029]FIG. 23 is an explanatory view showing a state of indirectimpression.

[0030]FIG. 24 is a schematic structural view of a refrigerator.

[0031]FIG. 25 is a schematic structural view of a refrigerator.

[0032]FIG. 26 is a schematic structural view of a refrigerator.

[0033]FIG. 27 is an explanatory view showing a state in which anelectrode shelf is set on the wall of the refrigerator.

[0034]FIG. 28 shows a perspective view of a terminal plate provided onthe wall of the refrigerator.

[0035]FIG. 29 is a perspective view of a shelf receiving portion of therefrigerator.

[0036]FIG. 30 is a side view of a vegetable room of a home-refrigerator.

[0037]FIG. 31 is a structural view of a space for accommodating theevaporator of a refrigerator.

[0038]FIG. 32 is a front view of a wire-electrode provided in a spacefor accommodating the evaporator shown in FIG. 31.

[0039]FIG. 33 is a structural view of an oil reduction device.

[0040]FIG. 34 is an explanatory view showing a state in which anelectrode is set in an electric fryer.

[0041]FIG. 35 shows a structural view of a gas fryer having an electrodetherein.

[0042]FIG. 36 is a perspective view of an electrode in the shape of acage.

[0043]FIG. 37 is a perspective view showing a state in which anelectrode is set in a gas fryer.

[0044]FIG. 38 is a perspective view showing another state in which anelectrode is set in a gas fryer.

[0045]FIG. 39 is a perspective view of the electrode shown in FIG. 38.

[0046]FIG. 40 is a perspective view showing still another state in whichan electrode is set in a gas fryer.

[0047]FIG. 41 is a perspective view showing still another state in whichan electrode is set in a gas fryer.

[0048]FIG. 42 is a structural view showing a state in which theelectrode shown in FIG. 41 is set in a gas fryer.

[0049]FIG. 43 is a perspective view of an electrode for a fryer.

[0050]FIG. 44 is a sectional view of another electrode.

[0051]FIG. 45 is a structural view of still another electrode.

[0052]FIG. 46 is a perspective view of a glass electrode.

[0053]FIG. 47 is a perspective view of a wire-electrode.

[0054]FIG. 48 is a perspective view of a glass electrode.

[0055]FIG. 49 is a perspective view of another glass electrode.

[0056]FIG. 50 shows a structural view showing a disposition of anelectrode in the oil tank of a fryer.

[0057]FIG. 51 is a sectional view showing a state in which an electrodeis buried in the tank wall of a fryer.

[0058]FIG. 52 is an explanatory view showing a state in which the tankwall of the fryer is insulated from the outer wall thereof.

[0059]FIG. 53 is an explanatory view showing another state in which thetank wall of the fryer is insulated from the outer wall thereof.

[0060]FIG. 54 is an expalnatory view showing still another state inwhich the tank wall of the fryer is insulated from the outer wallthereof.

[0061]FIG. 55 is an explanatory view showing a state in which anelectrode plate is set in a fryer.

[0062]FIG. 56 is an explanatory view showing a state in which anelectrode is set in a sushi-case.

[0063]FIG. 57 is a side view of an electrode set in a sushi-case.

[0064]FIG. 58 is an explanatory view showing a state in which a sensoris set on the door of a sushi-case.

[0065]FIG. 59 is an explanatory view showing another state in which anelectrode is set in a sushi-case.

[0066]FIG. 60 is an explanatory view showing still another state inwhich an electrode is set in a sushi-case.

[0067]FIG. 61 is a side view showing a state in which an electrode isset in a showcase.

[0068]FIG. 62 is an explanatory view showing a state in which anelectrode is set in a showcase.

[0069]FIG. 63 is a side view showing a state in which a glass electrodeis set in a showcase.

[0070]FIG. 64 is a perspective view of a glass electrode.

[0071]FIG. 65 is a side view of another electrode.

[0072]FIG. 66 is a perspective view of still another electrode.

[0073]FIG. 67 is a perspective view of still another electrode.

[0074]FIG. 68 is a perspective view of still another electrode.

[0075]FIG. 69 is a perspective view of still another electrode.

[0076]FIG. 70 is a perspective view showing a state in which a glasselectrode is set in a showcase.

[0077]FIG. 71 is a cross sectional view of a terminal plate used for ashowcase.

[0078]FIG. 72 is a sectional view showing a state in which a clip plateis connected to the end face of a glass electrode including a fine wiretherein.

[0079]FIG. 73 is a perspective view showing a state in which a terminalplate is put on a laminate electrode plate.

[0080]FIG. 74 is an explanatory view showing a state in which a terminalis connected to another glass electrode.

[0081]FIG. 75 is an explanatory view showing a case in which a terminalis connected to a normal glass plate.

[0082]FIG. 76 is an explanatory view showing a case in which a terminalis disposed in a showcase.

[0083]FIG. 77 is an explanatory view showing a case in which a terminalis disposed in a showcase.

[0084]FIG. 78 is a perspective view showing a state in which anelectrode is disposed in a rotary-sushi device.

[0085]FIG. 79 is a side view of the rotary-sushi device shown in FIG.78.

[0086]FIG. 80 is an explanatory view showing a state in which anelectrode is disposed on the way of a transport path of a rotary-sushidevice.

[0087]FIG. 81 is a perspective view showing a state in which a dryprotection device is disposed on the way of a transport path of arotary-sushi device.

[0088]FIG. 82 is a system structural view of a dry protection device ofa rotary-sushi device.

[0089]FIG. 83 is an explanatory view showing a state in which anelectrode is disposed in a refrigerator.

[0090]FIG. 84 is an explanatory view showing a system in which a chargedvoltage is changeable.

[0091]FIG. 85 is a structural view of a refrigerator in which a directcurrent power source is used as a high voltage generating device.

[0092]FIG. 86 is an explanatory view showing a state in which anelectrode is directly connected to a power source for domestic use.

[0093]FIG. 87 is a system view showing a state in which an electrodeplate and a spray pipe are disposed in an open showcase.

[0094]FIG. 88 is an explanatory view showing a control system for ashowcase.

[0095]FIG. 89 is an explanatory view showing a structure for making anelectrostatic field atmosphere in a large-size refrigerator.

[0096]FIG. 90 is an explanatory view showing a way in which a voltage isimpressed on potatoes and oranges.

[0097]FIG. 91 is an explanatory view showing a way in which a largeobject is treated in an electrostatic field.

[0098]FIG. 92 is an explanatory view of a needle which is used for theelectrostatic field treatment shown in FIG. 91.

[0099]FIG. 93 is a structural view of a prefab refrigerator.

[0100]FIG. 94 is a perspective view of a rack which is provided in aprefab refrigerator.

[0101]FIG. 95 is a perspective view of a fish box which is so formedthat an electrode is arranged therein.

[0102]FIG. 96 is a perspective view of an electrode with a battery.

[0103]FIG. 97 is an explanatory view showing a state in which anelectrode with a battery is arranged in a cardboard box.

[0104]FIG. 98 is an explanatory view showing a state to form anelectrostatic field in a refrigeration container.

[0105]FIG. 99 is an explanatory view showing another state to form anelectrostatic field in a refrigeration container.

[0106]FIG. 100 is a perspective view of the interior of a large-sizerefrigerator in which an electrostatic field is formed.

[0107]FIG. 101 is a perspective view showing a state in which anelectrostatic field is formed in a pallet.

[0108]FIG. 102 is a explanatory view showing a state in which cardboardboxes are piled on a pallet.

[0109]FIG. 103 is an explanatory view showing a state in which anelectrode is arranged in a cardboard box.

[0110]FIG. 104 is an explanatory view showing a state in which anelectrode is arranged in a cardboard box.

[0111]FIG. 105 is a perspective view of an egg accommodating plate.

[0112]FIG. 106 is an explanatory view of a germinating device in whichan electrostatic field is formed therein.

[0113]FIG. 107 is an explanatory view showing a state in which plantsare grown in an electrostatic field.

[0114]FIG. 108 is an explanatory view showing a state in which plantsare grown in an electrostatic field.

[0115]FIG. 109 is a perspective view of a cultivation cylinder in whichan electrode is arranged.

[0116]FIG. 110 is a perspective view of a cultivation cylinder in whichan electrode is arranged.

[0117]FIG. 111 is an explanatory view showing a way in which food isthawed in water.

[0118]FIG. 112 is an explanatory graph showing a thaw starting point.

[0119]FIG. 113 is an explanatory view showing a way in which food isthawed in water.

[0120]FIG. 114 is a structural view of an electrostatic field bath.

[0121]FIG. 115 is a structural view of a refrigerator for preservationof blood.

[0122]FIG. 116 is a structural view of an electrostatic field house.

[0123]FIG. 117 is a structural view of a raw flower preservation devicein which an electrostatic field is formed.

[0124]FIG. 118 is a sectional view of a dissolving furnace in which anelectrostatic field is formed.

[0125]FIG. 119 is a structural view of an engine in which anelectrostatic field is formed.

[0126]FIG. 120 is a structural view of an electron range.

[0127]FIG. 121 is a structural view of a muffler in which anelectrostatic field is formed.

[0128]FIG. 122 is a system view of pine weevil exterminating device inwhich an electrostatic field is formed.

[0129]FIG. 123 is a structural view of an electron-charged water supplydevice in which an electrostatic field is formed.

[0130]FIG. 124 is a structural view of a fish farm in which anelectrostatic field is formed.

[0131]FIG. 125 is a structural view of a water tank in which anelectrostatic field is formed.

[0132]FIG. 126 is a structural view of a maturing device in which anelectrostatic field is formed.

[0133]FIG. 127 is a graph showing a maturing state of pickles.

[0134]FIG. 128 is a sectional view of an electrostatic field water bed.

[0135]FIG. 129 is a structural view of a rice storage device in which anelectrostatic field is formed.

[0136]FIG. 130 is a sectional view of a large-size rice boiling pot inwhich an electrostatic field is formed.

[0137]FIG. 131 is a sectional view of a rice boiling pot for domesticuse in which an electrostatic field is formed.

[0138]FIG. 132 is a side view of an electrostatic field treatment table.

[0139]FIG. 133 is a sectional view of an electrostatic field cockpot.

[0140]FIG. 134 is a perspective view showing another embodiment of anelectrostatic field cockpot.

[0141]FIG. 135 is a circuit view of a high voltage generating device.

[0142]FIG. 136 is a circuit view of a high voltage generating devicewith a battery therein.

[0143]FIG. 137 is a view showing an alternating voltage outputted by thecircuit shown in FIG. 136.

[0144]FIG. 138 is a view showing a minus voltage of a high voltagegenerating device.

[0145]FIG. 139 is a circuit view of a high voltage generating device inwhich a safety device is arranged therein.

[0146]FIG. 140 is a circuit view of a high voltage generating device incase that a power source for domestic use is used as an earth.

BEST MODE FOR WORKING THE INVENTION

[0147] Embodiments of this invention will now be explained with refenceto drawings and tables. FIG. 1 is a view for showing an embodiment of athawing and freshness keeping device according to this invention.

[0148] A refrigerator has a heat-insulating material 2, an outer wall 5,and a temperature adjusting mechanism (not shown) therein. A metal shelf7 has a two-shelf structure, and objects such as vegetables, meat andfishes and shellfishes to be thawed, freshness-kept and matured are puton each shelf. The metal shelf 7 is insulated from the floor of therefrigerator by an insulating body 9.

[0149] Further, a high voltage generating device 3 can generate directand alternating voltages of 0-500 V, and the interior of theheat-insulated material 2 is covered with an insulating plate 2 a suchas vinyl chloride and the like.

[0150] A high voltage cable 4 for output a voltage of the high voltagegenerating device 3 is connected to the metal shelf 7 through the outerwall 5 and the heat-insulated material 2. When a door 6 provided on thefront face of the refrigerator 1 is opened, a safety switch 13 (see FIG.2) is turned off to stop the output of the high voltage generatingdevice 3.

[0151]FIG. 2 is a circuit view of the high voltage generating device 3.

[0152] AC 100V is supplied on the primary side of a voltage adjustmenttransformer 15. A numeral number 11 is a power source source lamp, and anumeral number 19 is a lamp indicating a state of operation. A relay 14is operated when the safety switch 13 is on with the door 6 beingclosed, and this state is indicated by a relay operating lamp 12. Theoperation of the relay closes relay contacts 14 a, 14 b, 14 c to impressAC 100V of a power source on the primary side of the voltage adjustmenttransformer 15.

[0153] An impressed voltage is adjusted by an adjusting knob 15 aprovided on the secondary side of the voltage adjustment transformer,and the value of voltage is indicated on a voltmeter. The adjusting knob15 a is connected to the primary side of a voltage increasingtransformer 17 provided on the secondary side of the voltage adjustmenttransformer 15, and the voltage increasing transformer 17 increases thevoltage, e.g., at a rate of 1:50. For example, 60V is increased to3000V. One output end O₁ on the secondary side of the voltage increasingtransformer 17 is connected to the meal shelf 7 insulated from therefrigerator through the high voltage cable 4, and the other output end02 is grounded. Further, the outer wall 5 is grounded, and, therefore, auser of the refrigerator 1 does not receive an electric shock even if hetouches the outer wall of the refrigerator. In case that the metal shelf7 is exposed to the interior of the refrigerator in FIG. 1, the metalshelf 7 must be separated from the inner wall of the refrigerator (airfunctions as an insulating material) because the metal shelf 7 must bemaintained in an insulating condition. However, in case that an object 8protrudes from the metal shelf 7 to contact the inner wall of therefrigerator, an electric current flows to the earth through the wall ofthe refrigerator, and, therefore, if the insulating plate 2 a applies tothe inner wall, the decrease of the voltage impressed thereon can beprevented. In addition, if the metal shelf 7 is covered with vinylchloride or the like with exposing the metal shelf 7 to the interior ofthe refrigerator, the whole of the interior of the refrigerator becomesan electrostatic field atmosphere. The interior of the refrigerator andthe metal shelf 7 may be painted and sprayed with known coating materialin addition to vinyl chloride and PBS.

[0154] Next, actual freshness keeping and maturing methods will now beexplained.

[0155] (A) Method of keeping freshness of vegetables (including fruits).If vegetables are basically stored at approximately 4° C., the freshnesscan be maintained, and, however, the vegetables are sometimes dried orwithered. In the case of cut vegetables, the cut portion thereof ischanged in quality and dried quickly. Temperature range for storage ischanged due to summer and winter vegetables. A alternating voltage isimpressed on the metal shelf 7 by the high voltage generating device 3,and, the voltage of the metal shelf 3, generated by the alternatingvoltage was determined as shown in Table 1. The voltage of the metalshelf 7 was measured by a known electrostatic measuring device. Thevegetables, meat and fishes and shellfishes were tested in such a mannerthat they were put in a stainless tray (having a good conductivity) withthe opening being covered with thin film. TABLE 1-1 Freshness keepingtest of vegetables and fruits Vegetables Freshness keeping device ofthis invention Conventional refrigerator Cucumber +1° C. No cutvegetables and cut vegetables were No cut vegetables and cut vegetables 500 V maintained fresh without browning and drying for browned anddried in five days and one or about two weeks and one week,respectively. two days, respectively. However, Cucumber ±0° C. No cutvegetables and cut vegetables were according to kind of vegetables, thetime 1000 V maintained fresh without browning and drying for period wasdifferent. about ten days and five days, respectively. Cucumber −1° C.No cut vegetables and cut vegetables were 2000 V maintained freshwithout browning and drying for about ten days and five days,respectively. Beefsteak plant −1° C. Freshness was maintained for aboutone week This vegetable withered in one or two days (big leaf)  500 Vwithout withering. and could not use as food. Beefsteak ±0° C. Freshnesswas maintained for about five days plant (big leaf) 1000 V withoutwithering Beefsteak leaf −1° C. Freshness was maintained for about fivedays (big leaf) 2000 V without withering Piment ±0° C. No cut piment andcut piment lost better taste in No cut piment and cut piment browned in2000 V about two weeks and a week without browning and about five daysand two days, respectively drying, respectively. Leek ±2° C. Freshnesswas maintained for one week The leek dried in one or two days.  700 V

[0156] TABLE 1-2 Freshness keeping test of vegetables and fruitsVegetables Freshness keeping device of this invention Conventionalrefrigerator Broccoli ±0° C. The broccoli did not brown for one week andbecame The stem yellowed in two days and did not 2000 V sweet. used asfood. Asparagas ±0° C. The stem did not change color and kept itsfreshness The stem changed color in one or two days. 2000 V Chinesegreen ±0° C. No cut chinese green was maintained fresh for ten days Nocut chinese green dried in about three 2000 V and cut chinese green keptits freshness for about one days and cut chinese green withered in halfa week. day. Chinese green +1° C. No cut chinese green was maintainedfresh for ten days 1000 V and cut chinese green was maintained fresh forfive days. Chinese green −1° C. No cut chinese green was maintainedfresh for ten days 3000 V and cut chinese green was maintained fresh forfive days. Cresson +1° C. Freshness was maintained for one week. Thecresson withered in about two days. 2000 V Cresson ±0° C. Freshness wasmaintained for one week. 2500 V Cresson −1° C. Freshness was maintainedfor five days. 3000 V

[0157] TABLE 1-3 Freshness keeping test of vegetables and fruitsVegetables Freshness keeping device of this invention Conventionalrefrigerator Carrot ±0° C. No cut carrot and cut carrot did not brownand yellow for No cut carrot and cut carrot browned in one 2000 V twoweeks and one week, respectively. week and two days, respectively.Pasley ±0° C. Pasley did not change color and maintained freshness forPasley changed color and dried in two days. 2000 V one week. Celery ±0°C. Celery did not change color and maintained freshness. Celery changedcolor and dried in two days. 2000 V Strawberry −1° C. Freshness wasmaintained for twenty days. Some of strawberry was changed quickly after500 V laying in stock, and the limit was three days. Grape ±0° C. Fruitsdid not drop from the cluster for twenty days, and Fruits dropped fromthe cluster for two or 1000 V stem did not brown. three days and thestem browned in one week.

[0158]FIG. 3 is a graph showing the relationship between the voltage andaverage temperature according to the results of the Tables 1-1 to 1-3.It can be understood that the freshness of vegetables is maintained fora long time at the ranges of average temperature of −2-+1° C. and ofvoltage of 500V-3000V in comparison with a conventional refrigerator.However, actually, a voltage less than 5000V is good. In the same kindof vegetable, at the proper respective ranges of the average temperatureand the voltage, when the voltage is increased, the average temperatureis decreased. When the voltage is decreased, the average temperature isincreased. Thus, a good result can be obtained. For example, in the caseof cucumber, if values of the voltage and the average temperature closeto a line of (+1° C., 500V), (0° C., 1000V) and (−2° C., 3000V) areselected, a good result can be obtained. Further, in the case of piment,broccoli, asparagas, chinese green, carrot, parsley and celery, a goodresult can be obtained near the line of (+1° C., 1000V), (0° C., 2000V)and (−1° C., 500V) and (−2° C., 1500V). According to the aboveconsideration, in the case of cucumber and beefsteak leaf, therelationship of Table 2 indicated below brings a good result. TABLE 2Temperature Voltage −2° C. 3000 V −1° C. 2000 V ±0° C. 1000 V +1° C. 500 V

[0159] According to the above results, it is understood that ifvegetables are stored on the metal shelf under the above condition usingthe apparatus shown in FIG. 1, they can be maintained fresh withoutfreezing at the range of temperature of minus or close to minus.

[0160] (B) Method of Thawing, Freshness-Maintaining and Maturing Meat

[0161] Thawing requires a large energy and the time period of thawingdepends on level of voltage. If the voltage is too high, an object to betreated may have stains and discolor. In the thawing apparatus, analternating voltage is impressed on the object in the same manner as thevegetables, and the alternating voltage is measured.

[0162] Some meat is freeze-stored at the temperature range of −55°C.-30° C. In case that meat is stored at a temperature less than −5° C.,the average thawing temperature is determined at the range of +0°C.-+10° C. and the alternating voltage of 3000V (3000V-5000V) isimpressed thereon to thaw frozen meat so that the core-temperature(temperature of the center portion) is raised to that upperapproximately −5° C. (the difference between the core temperature andthe outer surface temperature is less than 5° C.). Thereafter, a thawingoperation is done under the condition mentioned below. Time periodwritten in the columns of the thawing test of a thawing device of thisinvention means thawing time until an object becomes above −5° C. Thisis also adapted for thawing of fishes and shellfishes. TABLE 3 Thawingtest of meat Meat Thawing device of this invention Conventionalrefrigerator Roast beef ±0° C. Block of −15° C. was uniformly thawed fortwenty Thawing of the block required two days. (10 kg thawing)  2000 Vhours. There was a drip. There was a case in which the center portion ofthe block was still frozen. Roast beef −1° C. Block of −15° C. wasuniformly thawed for twenty (10 kg thawing)  3000 V hours. There was alittle bit of drip. Roast beef −2° C. Block of −15° C. was uniformlythawed for twenty (10 kg thawing) 45000 V hours. A slicer could slicethe block smoothly. Sirloin ±0° C. Block of −20° C. was uniformly thawedfor twenty-four Thawing of the block required two days and (5 kgthawing)  2000 V hours. There was a little bit of drip. fat yellowed.Sirloin −1° C. Block of −20° C. was uniformly thawed for twenty-four (5kg thawing)  3000 V hours. There was a little bit of drip. Sirloin −2°C. Block of −20° C. was uniformly thawed for twenty-four (5 kg thawing) 4500 V hours. Chicken +2° C. Chicken was thawed for one day with alittle bit of Chicken was thawed for one day with a (2 kg thawing)  2000V drip (1%). drip of more than 5%. Chicken +0° C. Chicken was uniformlythawed with a little bit of drip (2 kg thawing)  3000 V (1%). Chicken−1° C. Chicken was uniformly thawed with a little bit of drip (2 kgthawing)  4000 V (1%).

[0163] TABLE 4 Freshness maintaining and maturing Text Meat Freshnesskeeping device Conventional refrigerator Roast beef +1° C. Roast beefneither discolored nor made a drip for Roast beef discolored and made adrip in (freshness keeping) 300 V three days. It discolored on thefourth day. two days and there was putrid smell after two days. Roastbeef ±0° C. Roast beef neither discolored nor made a drip. It (freshnesskeeping) 500 V discolored on the sixth day. Roast beef −2° C. Roast beefneither discolored nor made a drip for one (freshness keeping) 700 Vweek. Sirloin +1° C. Sirloin matured in three days. Thereafter, it didnot Maturing of sirloin required for more than (ripening) 300 V discolorfor three days, and discolored on the fourth one week. day. Sirloin ±0°C. Sirloin matured in three days, and, thereafter, did not (ripening)500 V discolor for five days. Sirloin −2° C. Sirloin matured in threedays, and, thereafter, did not (ripening) 700 V discolor for five days.Chicken +1° C. Freshness was kept for three days, and color was Chickengot rotten in two days. (freshness keeping) 300 V changed on the fourthdays. Chicken ±0° C. Freshness was kept for five days. (freshnesskeeping) 500 V Chicken −2° C. Freshness was well kept for five days.(freshness keeping) 700 V

[0164]FIG. 4 is a graph showing characteristics between voltage andaverage temperature. It is understood that meat can be thawed in theaverage temperature range of −2-+1° C. and the voltage range of1000V-5000V with no stains, no discoloration, and a little bit of dripin comparison with a conventional refrigerator.

[0165] In the same kind of meat, at the respective proper ranges of theaverage temperature and impressed voltage, when the voltage isincreased, the average temperature is decreased. When the voltage isdecreased, the average temperature is increased. Thus, a good result canbe obtained. For example, in the case of roast beef and sirloin, if thevalues of the voltage and the average temperature are selected close toa line of (±0° C., 2000V), (−1° C., 3000V) and (−2° C., 4500V), a goodresult can be obtained.

[0166] According to the above consideration, in the case of roast beefand sirloin, the relationship of Table 5 indicated below brings a goodresult. TABLE 5 Temperature Voltage −2° C. 4500 V −1° C. 3000 V ±0° C.2000 V +1° C. 1000 V

[0167] According to the above results, it is understood that if frozenmeat is thawed on the metal shelf 7 under the above condition using theapparatus shown in FIG. 1, the meat can be thawed with a little bit ofdrip and in a state of high quality.

[0168] Further, it is understood that freshness keeping and maturing ofmeat require a rather short period of three days in comparison with aconventional refrigerator in the ranges of average temperature of −2-±1°C. and voltage of 300V-1000V, and meat can be maintained fresh for along time. In the same kind of meat, at the respective proper ranges ofaverage temperature and impressed voltage, when the voltage isincreased, the average temperature is decreased. When the voltage isdecreased, the average temperature is increased. Thus, a good result canbe obtained. For example, in the case of roast beef, sirloin (maturing)and chicken, if the values of the voltage and the average temperatureare selected close to a line of (+1° C., 300V), (±0° C., 500V) and (−1°C., 800V), a good result can be obtained. Further, measured data are notwritten here, and, however, a good result can be obtained even when thevoltage is increased to the level of 2000V.

[0169] According to the above consideration, it is understood that, inthe case of roast beef, sirloin and chicken, the relationship shown inTable 6 mentioned below is required. TABLE 6 Temperature Voltage −2° C.800 V ±0° C. 500 V +1° C. 300 V

[0170] According to the above results, if freshness keeping and maturingof thawed meat are done on the metal shelf 7 of the apparatus shown inFIG. 1 under the above condition, a good quality can be maintainedwithout discoloration for a long time in comparison with a conventionalapparatus.

[0171] (C) Method of Thawing and Freshness-Keeping Fishes andShellfishes

[0172] Both of thawing and freshness-keeping require a predeterminedvoltage, and in the case of quick thawing, the temperature is raised. Analternating voltage is impressed thereon in the apparatus in the samemanner as vegetable, and the alternating voltage is measured. Thefreeze-storage temperature is −30° C.-40° C. in the case of a slice of ahorse mackerel, −20° C.-30° C. in the case of scallop and −55° C. in thecase of tuna. Accordingly, in case that fishes and shellfishes arefreeze-stored below −5° C., first, the average temperature is determinedat ±0° C.-+1° C. and the alternating voltage of 3000V (2000V-5000V) isimpressed thereon to thaw them until the core-temperature (temperatureof the center portion) is raised to −5° C. Thereafter, thawing is doneunder the condition mentioned below. TABLE 7 Thawing test of fishes andshellfishes Fishes and shellfishes Thawing device of this inventionConventional refrigerator Frozen scallop +1° C. The scallop was thaweduniformly in twelve hours The scallop could be thawed in twenty(thawing) 2000 V with a little bit of drip. hours with drip and gettingout of shape. Some parts are thawed naturally. Frozen scallop ±0° C. Thescallop was thawed uniformly in fifteen hours (thawing) 2000 V withoutdrip. Frozen scallop −1° C. The scallop was thawed uniformly intwenty-four (thawing) 2000 V hours without drip. Shrimp without +1° C.The shrimp was thawed uniformly in twelve hours The shrimp could bethawed in twenty head (thawing) 2000 V with a little bit of drip. hourswith getting soft. (Normally, natural thawing and flowing water Shrimpwithout ±0° C. The shrimp was thawed uniformly without drip and thawingare used.) head (thawing) 2000 V getting out of shape. Shrimp without−1° C. The shrimp was thawed uniformly in twenty-four head (thawing)2000 V hours with a little bit of drip. Sole (thawing) ±0° C. The solewas thawed uniformly in fifteen hours The sole was thawed in twenty-fourhours 2000 V without drip. with drip. Tuna (thawing) ±0° C. The tuna wasthawed uniformly in twenty-four hours The tuna was not thawed at itscore portion 5000 V without drip. with surface thereof getting out ofshape. Crab (thawing) ±0° C. The crab was thawed in fifteen hours. Thecrab was thawed in twenty-four hours 2000 V with a specific smell ofthawing at the end of thawing (Normally natural thawing and flowingwater thawing are used.)

[0173] TABLE 8 Freshness keeping test of fishes and shellfishes Fishesand shellfishes Freshness keeping device of this invention Conventionalrefrigerator Scallop +1° C. There were no discoloration, a bad smell andThe fresh got hard with drip. (freshness keeping) 2000 V drip for twodays. Scallop ±0° C. There were no drip and a bad smell for three(freshness keeping) 2000 V days. Scallop −1° C. There were nodiscoloration, a bad smell and (freshness keeping) 2000 V drip for threedays. Raw oyster ±0° C. There were no discoloration and a bad smellThere was a bad smell in one or two (freshness keeping) 2000 V withoutthe shrinkage of flesh for five days. days. Heating was necessary forfood. Shrimp without +1° C. There were no discoloration and a bad smellfor There were discoloration and a bad head 2000 V five days. There wasa case that it discolored smell in two days. (freshness keeping) and hada bad smell on the fourth day. Shrimp without ±0° C. There were nodiscoloration and a bad smell for head 2000 V five days. (freshnesskeeping) Shrimp without −1° C. There were no discoloration and a badsmell for head 2000 V five days. (freshness keeping) Tuna +1° C.Freshness was kept for three days with a little Freshness was kept onlyfor one or (freshness keeping) 2000 V bit of drip. There was a case thatit discolored two days and it discolored quickly. on the fourth day.Tuna ±0° C. Freshness was kept for four days with a little bit(freshness keeping) 2000 V of drip. Tuna −1° C. Freshness was kept forfour days with a little bit (freshness keeping) 2000 V of drip.

[0174]FIGS. 5 and 6 is a graph showing characteristics of the voltageand the average temperature shown in Tables 7 and 8. It is understoodthat fishes and shellfishes, having a relatively high freezingtemperature, such as scallops, shrimps, etc., can be thawed in the rangeof the average temperature of −2-+1° C. and at the voltage ofapproximately 2000V without stains, discoloration and drip in comparisonwith a conventional refrigerator. Cuttle fish (squid) belong to thissort of fish.

[0175] According to the above consideration, it is understood that therelationship of Table 9 mentioned below is required for the thawing ofscallops, shrimps, etc. TABLE 9 Temperature Voltage −2° C. 2000 V −1° C.2000 V ±0° C. 2000 V +1° C. 2000 V

[0176] However, if the impressed voltage is determined at a voltage of1000V-4000V with the center voltage of approximately 2000V, a similarresult can be obtained. The condition in this case is the same as thatof freshness keeping mentioned after. In general, it is known that, withrespect to fishes and shellfishes, the period of thawing is decreasedwhen the voltage is increased, and is increased when the voltage isdecreased. A voltage of 3000-5000V is suitable for tuna.

[0177] According to the above results, it is understood that if frozenfishes and shellfishes are put on the metal shelf 7 of the apparatusshown in FIG. 1 to thaw them under the above condition, they can bethawed with a good quality and a little bit of drip.

[0178] Further, it is understood that fishes and shellfishes can bemaintained fresh, at the range of the average temperature of −2-+1° C.and at the voltage of approximately 2000V for a long time in comparisonwith a conventional refrigeration.

[0179] According to the above consideration, it is understood that therelationship of Table 10 mentioned below is required for freshnesskeeping of fishes and shellfishes. TABLE 10 Temperature Voltage −2° C.2000 V −1° C. 2000 V ±0° C. 2000 V +1° C. 2000 V

[0180] According to the above results, it is understood that if thawedfishes and shellfishes are put on the metal shelf 7 of the apparatusshown in FIG. 1 to be maintained fresh under the above condition, a goodquality can be maintained without discoloration for a long time incomparison with a conventional apparatus.

[0181] In the above measuring test, only alternating voltage isimpressed thereon, and, however, direct voltage may be impressed thereonat the above values of voltage to obtain the same results.

[0182] Further, in the measuring test, an electrostatic measuring deviceis used for measuring voltage impressed on the metal shelf. However,when the door is opened in actual thawing, freshness keeping andmaturing operation, a switch is turned off to cut a supply of thevoltage to the metal shelf. Therefore, the correspondence between theoutput voltage of a high voltage generating device and the electrostaticmeasuring device is measured to determine a predetermined voltage on themetal shelf based on a voltmeter for the output voltage of the highvoltage generating device. In addition, the suitable range oftemperature is −2° C.-+1° C., and however, data close to the measuredresult according to this invention were obtained even in the case oftemperature of −3° C.

[0183] In general, with respect to the freezing temperature of food, thefreezing temperature of fruits and vegetables is higher than that offishes and meat. The freezing temperature of these food depends on theimpressed voltage in an electrostatic field. When the voltage becomeshigh, the freezing temperature becomes low. It also depends on theamount of fat included in food. For example, the freezing temperature ofshrimps, crabs and cuttle fishes, etc. having a small amount of fat ishigher than that of tuna, sword fish, etc. having a relatively largeamount of fat. Accordingly, since the freezing temperature of an objectto be treated is established on the basis of the kind of the object andthe impressed voltage, the freezing temperature of the object to betreated is obtained on the basis of the relationship therebetween. Ifthe object to be treated is stored at a temperature between 0° C. andthe freezing temperature, preferably at a temperature close to thefreezing temperature, the object can be stored for a longer period oftime. That is, in the electrostatic field, the freezing temperature offood is lowered and the food does not freeze in the electrostatic fieldat the freezing temperature thereof in a conventional refrigerator.Therefore, it is easy to determine the temperature in a refrigerator.

[0184] With respect to the impressed voltage for keeping freshness,generally the voltage of 500V-1000V is suitable for vegetables,especially, leaf type vegetables as well as cakes and confectionery. Thevoltage of 1.5 kV-2 kV is suitable for beef and pork among meat.Further, the voltage of 500V-1500V is suitable for fruits.

[0185] In FIG. 1, the metal shelf 7 is set in an insulated state in therefrigerator 1, and, an insulated electrode 20 may be set on the shelvesof the refrigerator as shown in FIG. 8.

[0186] In FIGS. 8 and 9, the insulated electrode 20 according to thisinvention is in the shape of a plate, and has a connecting portion 22 toconnect a lead wire 21 to the electrode at its one corner. Theconnecting portion 22 is for connecting the lead wire 21 to a metalplate 28 in a sealed manner. Regarding the metal plate 23, any kind ofmetal can be used if it is conductive body. For example, a copper plate,a stainless plate or a titanium plate may be used. The metal plate 23 iscompletely insulated with an insulating coat 24 which is, e g., formedin such a manner that the metal plate 23 is dipped into a vinylchloridebath. Instead, the front and back surfaces of the metal plate 23 arecovered with insulating plates such as ABS resin with thecircumferential portions of the insulating plates being protruded fromthe edge of the metal plate 23 so that the protruded portions of theinsulating plates are heat-sealed. Further, since there is a case thatthe coating is damaged by the collision of the edge portion of the metalplate 23 with something, it is desired to provide an edge protectionmember 25.

[0187] In this manner, even if the metal plate (conductive body) iscovered with the insulating coating, negative electrons go outward tocharge environmental air with electrocity when a high voltage isimpressed thereon. When food is put thereon, the food is charged withelectrocity through the insulating coating to form a part of theelectrode plate. Thereby, the food functions as the electrode plate.

[0188] In addition, as shown in FIG. 10, a refrigerator has, therein, ashelf 26 which is so formed that metal bars are assembled in the shapeof lattice and to which a dipping treatment is performed.

[0189] In case that a voltage is impressed on the shelf 26, theinsulated connecting member 27 may be provided on a shelf bar in such amanner that the member bites the shelf bar. In this case, the connectingmember is formed as a clothespin, and has, at its biting portion, teeth28 which pass through the outer coating of the shelf bar to contact aninner metal bar directly In the opposite side to the biting portion, acompression spring 29 is provided so as to prevent the biting portionfrom becoming loose.

[0190]FIG. 11 shows another embodiment of a refrigerator 30 in which abare metal electrode 37 is put on a shelf 36 made of an insulatingmember in an insulating manner. An object to be treated is put on theelectrode 37. In this case, the electrode 37 may be supported in anyway, if it is supported in an insulating manner. In order to support theelectrode in the refrigerator 30 in an insulating manner, an electrode39 may be provided, as shown in FIG. 12, on the back side of a shelf 38made of an insulating member to expose the backside of the electrode 39to the air.

[0191] Instead, an electrode 39 may be covered with an insulating plate40. Materials such as air, plastic plates, Teflon plates, etc., areinsulating materials from the view point of electrocity, and they canmake an electrostatic field in an accommodating space.

[0192] A conductive electrode 42 may be set on a conductive shelf 41 viaan insulating member 41 made of an insulator, ceramic, Teflon, plastic,etc., as shown in FIG. 13. Further, as shown in FIG. 14, the main body44 of a conductive electrode may be held between insulating members.That is, in order to make an electrostatic field, the main body 44 ofthe electrode has at its lower side, an insulating member 45 forelectrically insulating it from a set member such as the shelf of arefrigerator and the like, and, at its upper side, an insulating contactprotection member 46 to prevent an operator from receiving an electricalshock. The two insulating members 44, 45 are so formed as to attachintegrally and uniformly vinyl chloride and the like thereon through,e.g., a dipping operation. Further, Teflon or ceramic may be attachedthereon by spraying or baking finish operation.

[0193]FIGS. 15 and 16 show an electrode 50 formed by dipping operation,which has a predetermined number of slits 31, 31, - - - 31. Theelectrode 50 comprises, as shown in FIG. 16, a main body 54 made of ametal plate with slits and an insulating material 55 made ofvinylchloride, etc. attached on circumferential surface of the main body54. If necessary, the edge portion of the electrode 50 may be protectedwith a protection frame 53. The formation of the slit 51 contributes toform a uniform coating layer. At the corner of the electrode 50 isprovided a connecting portion to which a high voltage cable 56 isconnected.

[0194]FIG. 17 shows an electrode unit 60 for changing easilyconventional refrigerator to an electrostatic field refrigerator, andthe unit 60 has a frame body 61 made of an insulating plastic plate. Theframe body 61 is inserted, as it is, in the space of the conventionalrefrigerator. The frame body 61 has left and right side plates 62, 62which are openable to a center plate 63, and on the inner faces of theside plates are provided supporting bars 64, 64 - - - 64, atpredetermined positions of which shelf plates 65 are detachablysupported. One of the supporting bars 64 is connected to a high voltagegenerating device 66, and a high voltage is impressed on the shelfplates 65 through the supporting bars 64. The center plate 63 and theside plates 62 have openings 67, 69 not so as to obstruct thecirculation of air in the refrigerator. If necessary, a bottom plate 68is provided, and a high voltage may be impressed on the insulated bottomplate 68. The supporting bars 64 and the shelf plates 65 may be coveredwith an insulating coating, and voltage is induced on the shelf plates65 even through the insulating coating in this manner. As shown in FIGS.18 and 19, slit portions 63 may be provided on the side plates 62 inorder to support slidably the shelf plates 65, and metal terminal plates67 may be buried in the upper and lower walls of each slit portion 63.Further, if the metal electrode plate 65 a is buried in the shelf plate65 covered with an insulating coating and the metal terminal plate 67 isopposed to the end portion of the shelf plate 65, a high voltage isimpressed on the shelf plate 65. In this manner, if the terminal plate67 connected to a high voltage generating device is opposed to the metalelectrode 65 a of the shelf plate 65 via an insulating coating, avoltage is induced indirectly on the metal electrode 65 a.

[0195] An indirect induction of voltage will now be explained in moredetail.

[0196] In FIG. 20, a terminal plate 71 is put on an electrode plate 70,and the terminal plate 71 is connected to a high voltage generatingdevice. The electrode 70 is so formed that a metal plate is covered withan insulating body 75. On the contrary, the terminal plate 71 is also soformed that a metal plate 77 is covered with an insulating body 76. Inthis manner, even if the metal plate 72 as the main body of theconductive electrode does not contact directly the conductive body (themetal plate 77) of the terminal plate 71 (if an insulating body existstherebetween), a voltage is impressed on the electrode 70. Either theelectrode 70 or the terminal plate 71 may have an exposed conductivebody without an insulating body.

[0197] The electrode 70 has, as shown in FIG. 21, therein a main body 72of the electrode, made of conductive film, aluminum foil and otherconductive bodies (fine wire, printing pattern) in an insulating body 75made of resin, glass, silicon, wood, paper, etc. Voltage impressed onthe electrode 70 is proportioned to the contacting area between theelectrode 70 and the terminal plate 71, and, therefore, as shown in FIG.22, if a triangular voltage adjusting plate 74 is attached to theelectrode 73 and the terminal plate 71 is moved to the left and right tochange the contact area between the voltage adjusting plate 74 and theterminal plate 2, a voltage impressed on the electrode 73 can beadjusted. The electrode 73 and the voltage adjusting plate 74 are soformed that, e.g., a conductive film is laminated by an insulating platesuch as vinylchloride and the like. The direct contacting area betweenthe electrode and the terminal plate 71 may be changed. Further, asshown in FIG. 23, a frame 78 may be provided on the end portion of theelectrode 70 so as to hold a bare conductive body 79 on the electrode 70therewith.

[0198] An insulated electrode of this invention can be adapted forrefrigerators 80 for business and domestic use shown in FIG. 24, andelectrode plates 85, 85 are put on the floors of refrigeration roomsarbitrarily selected. Further, when food is thawed in an electrostaticfield, it can be thawed at −2-−3° C. without drip, and, therefore, athawing room 83 may be provided in the refrigerator 80. The thawing room83 may have a planar electrode 85 mentioned above on its floor, and,however, a box-like electrode 86 in which an insulating plate is formedin a box with its entrance being opened. These electrode plate 85 andthe box-like electrode 86 are connected to a high voltage generatingdevice 84 provided at the lower portion of the refrigerator,respectively. The thawing room 83 can also function as a freezing room,and, e.g., when ice is made therein, the crystal of the ice becomessmall, so that the ice does not melt easily. Namely, this invention canbe adapted for a special apparatus for freezing and thawing.

[0199] Further, a refrigerator may be formed in the following manner. InFIG. 25, a refrigerator 90 has a casing 91 with a door-93. The innerwall of the casing 91 is coated with an insulating plate 94 and a metal(conductive) shelf 95 is made of, e.g., stainless and the like. Theshelf 95 is connected to a high voltage generating device 96 through ahigh voltage cable 97. Further, a shelf 95 having also a function as anelectrode 95 is held, in an insulating manner, by an insulating plate 94of the inner wall of the casing and air as an insulating gas in thecasing. A safety switch 13 (FIG. 2) is provided between the door 93 andthe casing, and a high voltage (500-5000V) is impressed on the shelf 95.In this manner, objects to be treated, such as meat, vegetable and fishare put and treated in an electrostatic field. Since the shelf 95 as anelectrode is held in an insulating state from the casing as an outerenvironment in air as an insulating gas, the accommodating space in thecasing forms an electrostatic field atmosphere. The objects 98 to betreated, on the shelf 95 must be also held, as a whole, in an insulatingstate. For example, if the objects contact the inner wall of the casingwhich is not insulated from an outer environment, electrons move intothe casing which is grounded, so that the objects are not charged withelectrocity. Therefore, it is necessary that the insulating plate 94must be attached to a part where the objects may contact the inner wallof the casing. However, in case that the inner wall of the casing itselfis made of insulating material, the insulating plate 94 is notnecessary.

[0200] According to the kind of vegetable and meat, the voltage forfreshness-keeping and thawing with respect to the temperature in therefrigerator must be changed. Therefore, a temperature sensor 99 isprovided in the refrigerator 1, and the detected signals by thetemperature sensor 99 are input to a driving circuit 100 which drives anadjusting knob 15 a on the secondary side of the voltage adjustingtransformer 15 to change the impressed voltage (FIG. 2).

[0201] Further, in case that meat and fish are thawed, a high voltage isnecessary when they are thawed in the state of a constant temperature,and, however, in the case of freshness-keeping after thawing, theimpressed voltage upon thawing promotes maturing too much. This is nogood for freshness-keeping. Accordingly, it is necessary to measurehardness of meat and fish to detect the finish of thawing, so that aproper voltage for freshness-keeping is determined. For example, it isfound that an impressed voltage of 5000V is preferable, at approximately−2° C., for beef upon thawing, and however, a voltage of 1500-2000V issuitable for freshness-keeping and maturing of beef. Therefore, a scale101 of hardness is set in a manner to make a probe contact the surfaceof meat to measure the repulsive force at that time, so that animpressed voltage can be adjusted according to the hardness signals.

[0202]FIG. 26 is a refrigerator 101 for domestic or business use, andthe refrigerator has an inner wall therein made of an insulating body111 such as plastic and the like. An electrode body 112 made ofconductive body, e.g., metal is buried in the insulating body 111 orattached to the backside thereof, and the electrode body 112 isconnected to a high voltage generating device. Each room of therefrigerator has a sensor for cutting impression of voltage when thedoor is opened. In order to charge the interior of a domesticrefrigerator with electricity, if a conductive thin film made of aplastic plate is attached to the backside of the inner wall thereof sothat a voltage is impressed on the thin film, there is no exposed parton which a high voltage is impressed to ensure safety. Further, theimpressed voltage of a vegetable room is low while that of a thawingroom is high. Therefore, impressed voltage of each room therein must bechanged according to the object of use. Even if only one high voltagegenerating device is provided, the impressed voltage can be changed soas to change the area of the conductive thin film which is attachedthereto or buried therein. Each room has a sensor 115 for detecting theamount of an electric line of force to sense an electrostaticatmosphere, and, when the sensor 115 detects that the amount of anelectric power is lowered more than a predetermined value, the sensor115 operates a refrigeration system 116 through a controller 117 to keepthe interior of the refrigerator at a plus temperature. That is, food isstored without freezing at a minus temperature in an electrostaticfield. In this case, if the electrostatic field is broken, the food isfrozen. Therefore, at this time, the refrigeration system is operated.Thus, such a control is necessary.

[0203] The wall 120 of a refrigerator has, as shown in FIG. 27, a shelfreceiving portion 121 which projects to the back side of a room, and theshelf receiving portion 121 has a slit 122 in which the end portion of ashelf plate 123 is slidably accommodated. The shelf plate 123 has anelectrode plate 124 which is covered with an insulating body 123 so thatan operator does not receive an electric shock even when the sensor 114does not work. The wall 120 comprises an insulating plate, and theprojected portion of the shelf receiving portion 121 is engaged with aterminal plate 130 in the shape of layed U as shown in FIG. 28. Theterminal plate 130 is connected to a high voltage generation device 130.Further, a voltage is induced by indirect contact between the terminalplate 130 and the electrode plate 124, and, in case that a voltage isnot impressed enough on the electrode plate 124, the end portion of theshelf plate 142 is formed thin to be inserted into the shelf receivingportion 121, as shown in FIG. 29, so that an enough voltage is inducedthrough the terminal plate 130. Further, the terminal plate 130 has, atits inner face, projections which correspond to a position of theinterior of the shelf receiving portion, where fingers of an operator donot reach, and an insulating material is removed from a slit insertingportion of the shelf plate so that the electrode plate 124 contactsdirectly the terminal plate 130. Thus, an enough voltage is impressedthereon.

[0204]FIG. 30 shows a vegetable room 150 of a refrigerator, which isdetachably accommodated therein. An electrode plate 151 is buried intothe circumferential wall of the vegetable room 150, and the vegetableroom 150 has, at its bottom, an electrode 156 which is so formed that anelectrode plate 154 is covered with an insulating coating 153. Theelectrode plate 154 is connected to a high voltage generating device155. Further, in case that a voltage is impressed enough on theelectrode plate 156, the vegetable room 152 is charged with electricitywithout the electrode plate 151 in the circumferential wall of thevegetable room.

[0205] In a domestic refrigerator, when a storing temperature isdetermined low, a necessary amount of electric power is increased.However, in an electrostatic field, even if the temperature in therefrigerator is determined at a temperature higher by 4-5° C. than anormal refrigerator, a similar result can be obtained. In addition, aflowing electric current is less than 2 mA for making an electrostaticfield in a refrigerator, and, therefore, an electric power consumptionis approximately 2W. It is ensured that even a low voltage (10V-100V)brings an effective freshness-keeping. It is not necessary that thetemperature in a refrigerator is determined at a minus temperatureexcept thawing, and a mode in which the temperature in the refrigeratoris determined at +5-+6° C. can be adapted in the case of inexpensivefood. Accordingly, as shown in FIG. 26, if a change-over switch 117 isprovided in a refrigeration system 116, and a switching operation isperformed between a freshness-keeping mode in which a coolingtemperature is kept low and a saving mode in which a cooling temperatureis kept high, energy is saved.

[0206] Further, in an electrostatic field atmosphere, since dew is notcondensed at a high temperature, as shown in FIGS. 31 and 32, it ispreferable that a high voltage (1500-2000V) is directly impressed on anevaporator 183 in a refrigerator or an electrostatic field is formed ina space in which the evaporator 183 is accommodated. That is, theevaporator 183 is provided at an upper and back portion in therefrigerator, and a fan 181 is provided above the evaporator 183 so thatcooling air is circulated in the refrigerator. A dash-board 185 isprovided in front of the evaporator 183. The inner wall of therefrigerator is made of an insulating material such as plastic and thelike, and a conductive thin film 182 such as alminium foil, etc., isattached to the inner wall thereof. Further, a conductive thin film 184is also attached to the side face of the dash-board 185 opposed to thatof the evaporator. There may be provided a conductive wire-likeelectrode 187, as shown in FIG. 32, between the dash-board 185 and theevaporator 183. Further, a plate-like electrode may be used. These thinfilm and the electrode 187 are properly provided as occasion demands,and a high voltage is impressed on these thin film, the electrode andthe evaporator 183 by a high voltage generating device 188.

[0207] It is found that edible oil is reduced in an electrostatic field,and, for example, as shown in FIG. 33, edible oil oxydized after cooking“tempura” (Japanese deep-fat fried food) is stored in a tank 160, and aninsulated electrode 161 as an oil reduction device is put into the oilto reduce the oil for two or three days to recover the oil to a goodcondition. The insulated electrode 161 has a bar-like core 161 a onwhich circular insulated electrode plates 161 b- - - 161 b are fixed ata predetermined space in the upper and lower direction. However, in thecase of a small amount of oil, a simple bar-like core 161 a may be used.Further, the core 161 a is connected to a high voltage generating device163. The insulated electrode may have any shape if it can make anelectrostatic field over the whole of the oil. Instead of the insulatedelectrode 161, an oil tank 160 may be put in an electrode box 162 inwhich a metal plate 164 connected to a high voltage generating device isburied, so that the oil is put in an electrostatic field. Theelectrostatic field prevents the oxidation of oil and, therefore, if oilis put in an electrostatic field, the oil can be stored for a long timewithout oxidation.

[0208] Next, a way in which an electrostatic field is given to a fryerfor cooking “tempura” and fry will be explained.

[0209]FIG. 34 shows an electric fryer 170 in which a heater 172 isinserted into an oil tank and taken out thereof by rotation of a handle171. Near the heater 172 is provided a plurality of electrode bars 173which are connected to a high voltage generating device 174. In thismanner, an electrostatic field can be made in oil in the oil tank. Thecasing of the oil tank is grounded, and, in case that a voltage of1500V-2000V is impressed on the electrode bars 173, even if an operatortouches the casing, he does not receive an electric shock. In case thata voltage of 100V-1000V is impressed on the electrode bar, earth is notnecessary for the casing. Even a voltage of 500V-600V can prolong theperiod of use two times. In case that the casing is not grounded, if avoltage impressed by a high voltage generating device 174 is lower thanthat in case that the casing is grounded, the same level of impressionvoltage on the oil can be obtained. This is because the amount ofelectric current dropping through the oil becomes small in the case ofno earth for the casing.

[0210] Next, in a gas fryer, an embodiment in which an electrostaticfield is made in oil as an object to be treated in order to decreasedeterioration of oil will be explained with reference to FIGS. 35 and36.

[0211] Oil 184 is accommodated in an oil tank 182 earthed in which acage-like electrode 180 is put through an insulator. When a high voltageis impressed on an electrode 180 by a high voltage generating device186, a high voltage electrostatic field is formed. At this time, an oiltank 182 is heated by a burner 183 to heat the oil to a predeterminedtemperature in a short time. If “tempura” is cooked in thiselectrostatic field, it can be cooked crisply, and the level ofdeterioration of oil is low to enable use of long time without change ofoil. In case that a bar-like electrode 187 is connected to a highvoltage generating device and the electrode 180 is formed as a simplecage 180, a voltage is induced to the cage 180 through the electrode187. In this case, the cage 180 functions as a supplementary electrode.

[0212] The mesh-like cage is convenient upon being put in oil, and ifthe mesh is fine, residuary substances after cooking “tempura” can beremoved by lifting the cage from the tank. In order to form a uniformelectrostatic field, a lattice in the shape of jungle jim may be put inthe cage-like electrode.

[0213] Since oil is an insulating material, if a metal electrode is putin oil in an insulating state, an electrostatic atmosphere is formed inoil located around the electrode. If “tempra” and fried food is puttherein, they are treated in an electrostatic field. However, when the“tempra” and fried food contact the inner wall of the oil tank 182, acharged state of the “tempra” and fried food is broken. At this time,the vertical circumferential wall 180 a of the cage-like electrode 180forms a dash-board for effectively preventing those from contacting thewall of the oil tank. In addition, the electrostatic field in the upperportion of the oil is weak only with the bottom wall 180 b of thecage-like electrode 180, and, however, the vertical wall 180 b preventseffectively the electrostatic field from becoming weak. With respect tothe earth of the gas fryer, it is the same as that of the electric fryershown in FIG. 34, and, in FIG. 35, the oil tank 182 is grounded.However, in case that a voltage impressed by a high voltage generatingdevice 186 whose one pole is earthed is low like a level of 100V-100V,it is not necessary that the oil tank 182 is grounded. The effects areas mentioned above.

[0214] In general, a gas fryer has heat pipes for heating oil in an oiltank. A case in which this invention is adapted for this type of the gasfryer will now be explained.

[0215]FIG. 37 shows the electrode of a fryer, and a bracket plate 191 isbridged between the right and left side walls 190. The side end 191 a ofthe bracket plate 191 is fixed on the upper surface of the side wall 190of the fryer. Support bars 193, 193 - - - 193 are disposed vertically ata portion of the bracket plate 191, opposed to the oil surface so as tobe located between the heat pipes 195, 195 - - - 195, and each supportbar 193 has an electrode plate 194. On the contrary, an electrode bar192 having a heat-resistance is provided close to the end portion of thebracket plate 191, and a high voltage is impressed on the electrodeplate 194 through the electrode bar 192, bracket plate 191 and thesupport bar 193. In this manner, since the electrode plate 194 islocated under the upper face of the heat pipes and between the heatpipes 195, an operator does not touch the electrode plates 194 to ensuresafety.

[0216] As shown in FIGS. 38 and 39, electrode plates 201 made of baremetal plates are disposed in the front and rear direction of the oiltank and under the heat pipes through insulating bodies 202, 202 in astate wherein they are fixed vertically to the wall of the oil tank toensure more safety. In this manner, if each electrode plate 201 is fixedvertically (upward and downward direction), it neither obstructscirculation of oil nor hold subsidiary substances of “tempra” and thelike when the oil is taken out of the oil tank. Further, one of aplurality of electrodes 201 has an electrode bar 205 in an uprightstate, and connecting bars 204 connect each electrode plate 201 witheach other. In addition, an electrode plate 210 may be fixed to asupport bar 211, through an insulating piece 214, which is fixed to amiddle portion of a bracket plate 212 which is installed on the endportion of the heat pipes 215, between adjacent heat pipes as shown inFIG. 40. As an electrode put in an oil tank, an insulated electrodeplate 260 may be used as shown in FIG. 41. That is, adapter plates 261,261 - - - 261 are provided uprightly at four corners of an insulatedelectrode plate 260 in which an insulating body is covered with a goodconductive body, and the upper end of each adapter plate is bentoutwardly to be hung on the upper surface T of an oil tank. Thereby, theinsulating electrode 260 is held at a position where the insulatingelectrode 260 does not contact heat pipes in the oil tank. The electrodeplate 260 is treated with coating such as Teflon, ceramic and the likeor complex coating thereof, and is provided with a plurality of openings260 a, 260 a, - - - 260 a, and a lead wire L from a high voltagegenerating device not shown is connected to one of the adapter plates261.

[0217] In the case of no adapter plates 261 shown in FIG. 41, aplurality of projections 273 may be formed on the oil tank 272 as shownin FIG. 42 to hold the insulating plate 260 therewith. In this case, aconnecting bar 276 is provided uprightly to be connected to a lead wire275.

[0218]FIG. 43 shows an electrode 286 in which heat-proof Teflon plates280, 280 (having a heat-resistance of 260° C.) are joined at a spacewith spacers 2281, 281 - - - 281 to accommodate therebetween the mainbody 282 of the electrode 286. A connecting pin 284 is provideduprightly at a corner of the electrode main body 282 to be engaged witha connecting terminal which has a jack portion at the lower end portionof a Teflon bar 283, and a lead wire 285 is extended from the upper endof the Teflon bar. The Teflon plate 280 has a cut portion 287 at onecorner so that the electrode main body 282 can be accommodatedcompletely between the two Teflon plates. The electrode main body 282and the Teflon plates 280 have openings 0, 0, - - - 0 to be registeredwith each other for ensuring a: circulation of heated oil in the oiltank.

[0219]FIG. 44 shows an electrode 240 of another type of fryer which hasa metal electrode 242 with circulating holes 241, and the metalelectrode 242 is held detachably in a cover plate 245 which has legportions 245 a and is made of, e.g., china, porcelain, insulator,ceramic and the like. The cover plate 245 has holes 244 in registrationwith the holes 241. The leg portions 245 a of the cover plate may beprovided at both side ends of the cover plate 245, opposed to eachother. Further, the leg portions 245 a may be provided at three sides ofthe cover plate 245 so that the metal electrode 242 can be put into andtaken out of the remaining one side of the cover plate 245. The coverplate 245 is held on a metal net 246 mounted on heat pipes 247. Theupper surface of the electrode 242 is protected by an insulating body,and, therefore, a tool which an operator uses does not contact theelectrode 242 on which a high voltage is impressed directly.Furthermore, the lower surface of the electrode 242 is opened to oil, sothat sufficient electrostatic field is formed in the oil. The electrode242 is connected to a high voltage generating device not shown through aconnecting bar 248. Further, as shown in FIG. 45, two left and right legmembers are prepared and an electrode plate 252 is put between a legportion 251 of the leg member 250 and an insulating cover plate 253which are screwed with each other to form an electrode 255. Thisfacilitates its manufacturing.

[0220]FIG. 46 shows an electrode 310 in which a heat-resistance glasstube 315 is deformed by heat in a desired shape, and a metal wire 316 asa conductive electrode is passed through the tube 315. The both ends ofthe electrode 310 are extended upwardly, and a lead wire 318 isconnected to the entrance side thereof while the exit side thereof isclosed by a plug 319. Subsidiary substances of “tempra” and fried fooddo not adhere such a glass electrode easily, and the glass electrode hasa beautiful appearance.

[0221] An electrode for generating an electrostatic field in an oil tankmay be formed as an electrode 320, as shown in FIG. 47, in which aconductive wire-like or bar-like electrode main body 325 is coveredwith, e.g., heat-proof and insulating coating 326 to be bent in variousshapes. In case that this shape of electrode is used in a refrigerator,the insulating coating may be plastic such as vinylchloride, etc., and,however, in case that it is used in a fryer, Teflon or ceramic layereach having a heat-resistance is preferable. The electrode 320 can beformed inexpensively if the electrode main body 325 is inserted into aconventional vinylchloride or Teflon tube to be bent by a bender.

[0222] If a conductive body such as iron powder and copper powder andthe like as well as a connecting wire 292 is put into a heat-proof glasstube 290 to form an electrode for a fryer, the drop of impressed voltagethereon is decreased, and the electrode does not move easily in oilbecause of the increase of its weight (FIG. 48). Further, as shown inFIG. 49, when the drop of impressed voltage is large, a number of smallholes-301 may be formed on the glass tube. Also in this case, instead ofthe connecting wire 302, silver plating may be performed to form anelectrode. Such a glass electrode can be used to form an electrostaticfield in water.

[0223] The above is an explanation for a case in which an electrode isinserted into an oil tank to charge oil with electricity, and, however,a high voltage is impressed on an oil tank itself. That is, a fryer 200has, as shown in FIG. 50, an outer casing 221 in which an oil tank 222is accommodated, and heat pipes 224, 224, - - - 224 are provided in thelower portion of the oil tank 222. Insulating electrode plates 223 - - -223 are adhered on the outer wall of the oil tank 222 to form anelectrostatic field in the oil tank. As shown in FIG. 51, the whole partof the oil tank may be formed as an electrode in such a manner that ametal plate 231 is covered with an insulating coating 232. The oil inthe oil tank is heated to a high temperature (160-200° C.), and,therefore, the insulating coating 232 must be heat-proof, and, forexample, Teflon, ceramic or a complex coating thereof is used. In thesecases, the oil tanks 222, 230 are supported in an insulated state withrespect to the outer casing 221. Concretely, as shown in FIG. 52, aconnecting member 225 made of an insulating body is provided along thecircumferential portion of the oil tank and at the upper portion of thewall 222 a of the oil tank, and the connecting member 225 is connectedto an upper wall 222 b which is supported on the outer casing 221. Ahigh voltage generating device may be directly connected to the wall 222a of the oil tank. The connecting member is formed in hook-shape of L,as shown in FIG. 53, and the hook-shaped upper portion of the wall 222 aof the oil tank is hung on the lower portion of the connecting member,so that the leakage of oil from the connecting portion of the tank wallcan be prevented. The upper bent portion of the oil tank 222 may beconnected to the outer casing 221 through an insulating body as shown inFIG. 54. In this case, a voltage is also impressed on the upper bentportion, and, therefore, a voltage of approximately 500-700V isimpressed thereon. A user does not acknowledge an electrostatic field tobe safe with such level of voltage. Accordingly, at this time, the earthof the oil tank is not necessary. The oil tank wall and heat pipes aregenerally connected, by welding, with each other, and a high voltage isalso impressed on the heat pip No cut vegetables es to form uniformly anelectrostatic field in oil in the oil tank In the case of a relativelylow voltage (300V-700V) as shown in FIG. 55, even if an operator touchesa bare metal electrode plate 260 with metal chopsticks, he does notreceive an electric shock. Therefore, for example, one pole of thesecondary side of a high voltage generating device 261 is earthed, and,however, the casing 262 of the oil tank is not necessarily earthed tofacilitate its construction work. In this manner, even a relatively lowvoltage can prevent the oxidation of oil to extend the life span of oilat least two times without electric shock of an operator. The electrodeplate 260 is made of a stainless plate and has a number of openings 263and insulating pieces 264 - - - 264, at its corners, which are made ofceramic or Teflon and which are protruded outwardly so that theelectrode plate 260 does not contact the circumferential wall of the oiltank. The insulating pieces 264 function to hold the electrode plate 260in an insulating state from the heat pipes in the oil tank, and aninsulating piece is provided on the center of the backside of theelectrode plate 260 as occasion demands.

[0224] Also in the case of a relatively low voltage, there is no doubtthat only the upper surface of the electrode plate 260 may be coveredwith an insulating material or a coating. The insulating materialeffectively functions to prevent an operator from touching directly theelectrode plate with chopsticks, and it is preferable that the backsurface thereof is opposed to the oil because the oxidation of oillocated under the electrode plate is effectively prevented.

[0225]FIG. 56 shows a fish case as a food storing apparatus which has aninsulating electrode 231 which is provided with a screen bulkhead 232 infront of which ornaments such as leaves of Japanese cedar or bamboo arelocated. The screen bulkhead 232 is for avoiding contact between anobject 234 to be treated and the frame of the fish case which isgrounded so that the object is not grounded. An earthed part, e.g., railof the fish case, located under the opening door 235, where a hand maytouch is insulation-treated (the rail itself may be made of or coveredwith an insulating body) so that the object on the electrode 231 is notgrounded even when an operator grasps that object in a state wherein hishand contacts the rail simultaneously. The insulated electrode 231 maybe one shown in FIG. 15 and one in which a conductive film is laminatedwith upper and lower plastic plates. In the laminated type of electrode,a method of connecting an electrode as shown in FIGS. 20 and 21 ispreferable. The insulating electrode 231 is connected to a high voltagegenerating device 237 to form an electrostatic field in an space foraccommodating a cooling device at the lower portion of the fish case byadhering a conductive thin film 236 on the circumferential wall of thespace and to function to prevent dew condensation for the coolingdevice. As shown in FIG. 57, the front portion of the electrode 231 maybe bent backward.

[0226]FIG. 58 shows a back face of a fish case in which sliding doors240, 241 and proximity sensors 244, 244 are provided on the left andright sides of an upper frame 245. When either the door 240 or 241 isopened, the impression of voltage on the electrode 242 from a highvoltage generating device 243 is stopped. Instead of the proximitysensors, limit switches may be provided.

[0227]FIG. 59 shows a fish case which is installed in asushi-restaurant, and on its bottom face is provided an insulating plate250 on which fishes are put. Further, an electrode bar 281 is disposedin a space of the fish case, and the electrode bar 281 is connected to ahigh voltage generating device not shown. The electrode bar may be soformed that silver plating is performed in a hollow glass tube and alsothat a copper wire is disposed in the hollow glass tube. Such anelectrode bar 251 can be also disposed in a refrigerator. In thismanner, an electrostatic field can be formed in the whole part of thefish case.

[0228] However, as shown in FIG. 60, an object 280 to be treated, put ona dish d in the fish case often contacts the circumferential wallthereof, and, if the contact part is conductive body, the voltageimpressed drops therefrom. Therefore, it is preferable that at least anupper frame 281 is made of an insulating material, and an electrodeplate 282 is attached to the center of the back side of the upper frame281. In addition, the upper frame 281 has a glass plate 283 and a glassdoor 284 (the rear portion of the upper frame 281 is formed as a rail),and a cooling device 286 is accommodated in a lower frame 285 supportingthe upper frame 281. An electrostatic field is so formed in the space ofthe lower frame 285 as to prevent effectively frost attachment on thecooling device.

[0229] Next, a showcase having an electrostatic field therein will nowbe explained.

[0230]FIG. 61 shows a showcase (open case) 400 having upper and lowershelves 402, 402 therein on which insulated electrode plates 401, 401are mounted, and food 403 is located on these electrode plates. Any foodsuch as fishes, vegetables and cakes, etc., can be freshness-kept. Onthe top plate of the showcase is mounted a high voltage generatingdevice 405 to which electrode plates 401, 401 are connected through leadwires 404, 404 and which is grounded through an earth wire 406. Ingeneral, a voltage of 2000-5000V is impressed on the electrode plates401 by the high voltage generating device 405.

[0231] In the case of the showcase, an electrode plate whose wholesurfaces are covered with an insulating coating is not necessarily used,and, as shown in FIG. 62, a shelf itself made of an insulating body mayholds a metal plate 410, in an attaching state on its backside so as toexpose the lower face of the metal plate 40 to air. Furthermore, theshelf itself may be made of an insulating body, and the metal plate 410may be pushed into the insulating shelf. In many cases, vegetables aretreated with an impressed voltage of 10V-700V, and, in this case, a baremetal plate may be put on the shelf. At this time, an operator neverfeels an electric shock, and the showcase itself does not need an earth.

[0232]FIG. 63 shows a showcase 420, and, in the case of meat and fish itis preferable that, a shelf is so formed that a metal plate is coveredwith an insulating body. However, in the case of western cakes andJapanese cakes 422, a glass shelf or a transparent shelf is generallyused. An electrostatic field of a voltage of 300-600V is optimum forfreshness-keeping of cakes, and, in this case, as shown in FIG. 64,metal fine wires 430 are disposed in a transparent or opaque glass plateor acryl plate so as to be connected to a lead wire 432 through aconnecting portion 431 for impressing a voltage on the fine wires 430.The electrode 433 thus formed can be used as a shelf itself. In casethat metal fine wires located at the circumferential edge of the glassplate are exposed barely, an insulating circumferential frame isattached thereto. However, in the case of 500-700V, the frame is notnecessarily provided. Further, a metal foil such as aluminum or tin maybe attached to the whole surface of a glass plate or a resin plate sothat a voltage is impressed on the metal foil. Instead, metal may beevaporated on an insulating plate.

[0233] Further, as shown in FIG. 66, an electrode 451 may be so formedthat a resin film 450 having a conductive pattern, on its inner surface,obtained by evaporation or printing is adhered on a glass or resin plate453. In addition, the electrode may be so formed that printing isperformed on the glass plate 453, or conductive ink or coating materialis painted on the glass plate 453 or the film 450. Metal film may beformed by evaporation. Instead of the glass plate, a conductive film orpattern may be formed on various insulating materials such as china,stone, etc., by various means. An insulating ink coating material may bemixed with conductive powders to be printed or painted on an insulatingmaterial. Instead of the film 450, a conventional film (tape) may beattached thereto, and an insulating thin film may be further attached ona metal foil which is adhered on a glass plate 453.

[0234] As an electrode used in an open case or a flat case for asupermarket, as shown in FIG. 67, the electrode is so formed that aconductive pattern 461 is printed or evaporated on an insulating film460 such as vinylchloride resin. This kind of electrode is usefulbecause it has a certain level of strength. A conventional thin film 464for protection of charging may be used as an electrode so as to beprotected with other members (FIG. 68). A laminate type of electrode canbe used, as shown in FIG. 69, in such a manner that a conductive film471 is held between two upper and lower plastic films whosecircumferential portions are adhered with each other.

[0235] Next, a case in which a glass electrode is installed in ashowcase will now be explained.

[0236] As shown in FIGS. 70 and 71, it is preferable that a longterminal plate 481 is located under a glass electrode plate in aninsulated state. This terminal plate 481 has a stainless plate 482 whoseside and lower surfaces are covered with an insulating coating 489. Ifthe upper face of the stainless plate 482 contacts directly the lowerface of the glass plate, the drop of voltage is little. On the contrary,if the upper face of the stainless plate 482 is covered with aninsulating plate, a voltage impressed on the glass electrode plate 480decreases. However, if the terminal plate 481 is formed long in alongitudinal direction of the glass electrode plate, the glass electrodeplate 480 can be easily accommodated in a showcase in a state whereinthe glass electrode plate is divided in its longitudinal direction. Theglass electrode plate 480 is put on the terminal plate 481 which is puton an insulating plate 481 which is put on an insulating plate 485 madeof vinylchloride which is put on a support frame 484 provided on bothsides of a showcase. The circumferential face of the glass electrode 480is ground to avoid danger of fine wires.

[0237]FIG. 73 shows an laminated electrode plate 500 used instead of theglass electrode plate 480, and the electrode plate 500 is so formed thata conductive sheet 501 is laminated with an insulating plastic. When avoltage is impressed on the laminated electrode 500, a terminal plate502 is just put thereon. In case that a sufficient voltage cannot beobtained with an indirect contact, a hole 503 is provided in alaminating plastic film in order to expose the conductive sheet outward,and a conductive body such as conductive paints are buried in the hole503 so that the conductive body contacts the lower face of the terminalplate 502. The terminal plate 502 is so formed that a metal plate iscovered with an insulating coating. The insulating coating of theterminal plate is partly removed to expose the metal plate outwardly,and the metal plate is directly brought into contact with the conductivesheet 501 of the laminated electrode plate 500 through an intermediateconductive body such as conductive paints to decrease dropping of animpressed voltage. The lowest step of the showcase forms a floor, andglass is not used for the floor. Therefore, the laminated electrode 501is used instead of the glass electrode.

[0238] Instead of the terminal plate 502, there may be used a connectingtool 504 on the bottom face of which teeth 504 a are projectinglyformed. The teeth 504 a bite the laminated electrode so as to project tothe backside thereof, and the projected portions of the teeth are bentto prevent them from coming out. In this method, the teeth 504 a contactdirectly the conductive sheet 501 so that a voltage can be surelyimpressed thereon.

[0239] In order to impress a voltage on the glass electrode plate 490,as shown in FIG. 72, conductive paints are coated or sprayed to form aconductive layer 492 which contacts the distal end exposed at the sideend face of the glass electrode plate 490 and-to which a chip plate 494is connected through a conductive rubber 943. The clip plate 494 isprovided with cable receiving portion 476 to which a cable 497 isconnected, and the cable 497 is connected to a high voltage generatingdevice not shown.

[0240]FIG. 74 shows a glass electrode 530 for a showcase, on whichconductive tapes 532, 532, 532 are adhered, on the end portion of whicha connecting tape 533 is provided to connect each conductive tape witheach other. A connecting terminal 534 of layed U-shaped in section isdetachably attached on the tape 533, and the terminal 534 is connectedto a high voltage generating device.

[0241] It is possible that the glass plate 531 is charged withelectrocity in such a manner that an insulated metal terminal 531 isattached to the frame 530 of a conventional showcase, and a glass plate532 (conductive treatment is not performed) is simply put on theterminal plate 531. The terminal plate 531 can be set on a frame notshown on the opposite side of the glass plate 532. In this case,strength of charge is large at a position close to the terminal plate531 and the strength of charge becomes small as a position goes far fromthe terminal plate 531.

[0242] Further, the installation of an electrode plate on a showcasewill now be explained.

[0243] As shown in FIGS. 76 and 77, a terminal plate 541 connected to ahigh voltage generating device 542 is put at the bottom of the showcase,open case or flat case, and an insulating electrode is put on theterminal plate 541. Terminal plates 542, 542 connected to a high voltagegenerating device 545 can be set on the floor of the showcase so as tocontact the electrode plate. This way is suitable for the laminatedelectrode shown in FIG. 69.

[0244] Next, the formation of electrostatic field on a rotarysushi-apparatus will now be explained.

[0245] In FIGS. 78 and 79, a numeral number 550 shows a counter of therotary sushi-apparatus, and a conveyor 551 in the shape of scales isinstalled adjacent the counter 550. A dish 552 is set on the conveyor asa transfer path, and has a sushi 553 thereon. The counter is grounded,and a pipe-shaped electrode 554 is disposed over the conveyor so as tobe supported by a support 555. The electrode 554 is preferably so formedthat a good conductive metal is evaporated on the inner surface of thestrenghened glass because of a good appearance. A high voltage (1 kV-3kV) is impressed on the electrode 554 to form an electrostatic fieldaround the electrode 554. Since the electrode 554 is formed in aninsulating glass body, a guard 556 is not necessarily required and,however, the guard 556 is preferably provided to prevent hands of guestsfrom contacting the electrode for more safety. Instead of thetube-shaped electrode 554, a normal wire or plate may be used, that is,any conductive bodies can be used. The electrode may be so formed that aconductive body is simply covered with an insulating coating or thatconductive body is exposed to air. The guard 556 is not necessarilyrequired in the case of the electrode covered with the insulatingcoating. The electrode 554 may be provided, as shown in FIG. 80, at apart of the transfer path to form an electrostatic field treatmentportion 561 without being provided over the whole of the sushi-transferpath. The electrode 554 is not necessarily provided over the transferpath, that is, it may be provided under and on the side of the transferpath, at any place so long as an electrostatic field is generated.

[0246] The electrostatic field treatment apparatus functions to preventfood from drying. Further, for prevention of drying, as shown in FIGS.81 and 82, if an electrostatic field is formed in a semicylindrical dome572 which functions as a drying preventing apparatus for covering a partof the conveyor 551 therewith and fine waterdrops are attached to thesushi 553, drying of sushi can be effectively prevented. That is, anelectrode 554 is provided in an upper space of the semicylindrical domein its longitudinal direction, and a high voltage generating device 526is connected to the electrode 554. The electrode 554 may be so formedthat a metal coating is adhered on the interior of a hollow tube or maybe a hollow conductive bar. In its dome 572 is provided a spray tube 570in the shape of arch, on the inner circumferential surface of which anumber of fine holes are provided. The spray tube 570 is connected to asupersonic wave spray apparatus 574, through a tube 573, which has awater tank 575 connected to a high voltage generating device 576.Thereby, electron-charged water is made. As a method of making theelectron-charged water, the water may be so made that an electrode isdirectly inserted into water or it is attached to the outer wall of thewater tank in a state wherein the whole of the water tank 575 is in thestate of insulation. The electron-charged water is changed into finewaterdrops, by a supersonic vibration, which are supplied to theelectrostatic field atmosphere from the spray tube 570 through the tube573 to be charged with electrocity and to be attached on the sushi 553charged with a reverse voltage. A suction tube 572 may be provided at aproper position to prevent the waterdrops from flowing out of the dome570.

[0247] Next, the disposition of an insulating electrode in arefrigerator or case will now be explained.

[0248]FIG. 83 shows a refrigerator (case) 580 as a food storingapparatus in which three electrodes 581, 582, 583 forming three shelvesare disposed in an upper and lower direction (the shelf itself is anelectrode plate), and the center electrode 582 is connected to a highvoltage generating device 584. An electrostatic field is generated atupper and lower positions of the electrode plate 582 to induce the upperand lower electrodes 581, 583. The induced voltage of the electrodeplates 581, 583 is inverse proportion to the square of distance Wseparated from the center electrode 582. That is, as the distance Wbecomes large, the voltage in the electrostatic field decreases to lowerthe induced voltage. If the distance W separated from the electrodeplate 582 connected to the high voltage generating device 584 isadjusted in this manner, the adjustment of voltage impressed on anobject 586 to be treated becomes possible. In this case, the upper andlower electrode plates 581, 583 are simple shelves, and, however, theymust be held in the refrigerator in an insulated state. If the uppershelf 581 is grounded by an earth wire 587, the voltage drops throughthe shelf 581, and, therefore, the upper position of the shelf 581 isnot charged with electricity. Namely, if it is desired that a part ofthe refrigerator is not charged with electrocity, the part is partlygrounded. Especially, alcohol is matured in a refrigerator for domesticuse. If the maturing of alcohol is not desired, a room for alcohol isgrounded to protect the influence from an electrostatic field. Forexample, in a refrigerator, a voltage of 5000V is impressed on thelowest shelf connected to a high voltage generating device to use thelowest, intermediate and the upper shelves for thawing,freshness-keeping and freshness-keeping, respectively. Namely, when thethawing of an object on the lowest shelf is finished, it is moved to ashelf of low voltage on which a voltage is not directly impressed forfreshness-keeping. The optimum voltage depends on the kind of vegetableand meat, and, therefore, various voltages can be impressed on shelvesin a refrigerator according to the above way. At a proper position ofthe refrigerator is provided a light sensor 585 by which the highvoltage generating device 584 is turned off when a door is opened. It ispossible that the high voltage generating device 584 is connected toeither the upper or lower electrode plates 581, 583. As shown in FIG.84, the voltage impressed on each electrode can be adjusted in a mannerthat the kind of materials of insulating coatings for the electrodeplates 601, 602, 603 disposed in various ways is changed.

[0249]FIG. 85 shows an electrostatic treatment method of using a highvoltage generating device of direct current, and a shelf 593 forming aninsulating electrode has a pan 594 thereon in which an object 595 to betreated is accommodated. The pan 594 is connected to a switch circuit592 which is connected to a wall of a refrigerator and a high voltagegenerating device 590 and also connected to a sensor 591 provided on thedoor of a refrigerator. When the door is opened, a switch circuit 592 isturned on, and the pan 594 is grounded. In the case of the use of adirect current electric power, electric charge of the same pole isstored in the object 595, and it is necessary that the object 595 isdischarged through the pan 594. In the case of the use of a bareelectrode 593, the pan 594 is not necessary, and the electrode 593 isdirectly connected to the switch circuit 592. Normally, electric chargeis changed alternately to plus and minus values to be preferablyneutralized, and a direct electric current is suitable for some objects.It is found that the freshness of plants such as fruits, flowers, etc.can be kept in a weak electrostatic field, and, therefore, as shown inFIG. 86, the electrostatic field treatment apparatus may be so formedthat a normal domestic electric power (100V) is connected to aninsulating electrode 610 through a safety device 611 for prevention ofan overcurrent. This apparatus can be effectively used as anelectrostatic field mattress. That is, the electrode 610 may be formedas a thin electrode plate to be set between a sheet and a mattress.Furthermore, it can be adapted for a cushion and a bustle for a chair.Food including much water such as malts and radishes can befreshness-kept by a voltage of less than 100V, and, therefore, in thiscase, a domestic electric power of 100V is used so that the voltage isdecreased with a transformer.

[0250]FIG. 87 shows an open case for a supermarket.

[0251] An open case 653 has shelves 650, 650, 650, on which electrodeplates 651 are mounted, and objects 652 to be treated are put on theelectrode plates 651 which are connected to a high voltage generatingdevice 654. At the front and above position of the open case 653 isprovided a spray member 655 to which waterdrops are supplied from asupersonic spray device 656, and the fine waterdrops sprayed from aspray tube are charged with electrocity by an electrostatic atmosphereformed above the shelves so as to be attached to food displayed on theshelves. Since the electrostatic field has an antibacterial function,the waterdrops sprayed can be effectively prevented from being pollutedfrom bacillus. If an electrostatic field is formed in the supersonicspray device 656 to make electrostatically charged water therein, moreeffect can be obtained.

[0252]FIG. 88 shows a closed-type showcase 660 in which insulatingelectrodes 663, 663 are put on the shelves 664, 664 of the showcase, andthe electrodes are connected to a high voltage generating device 667.Instead of (or In addition to) an electrostatic atmosphere being formedin the showcase by the insulating electrode 663, electrode bars 661, 662which are connected to a high voltage generating device 667 may bedisposed in the showcase. In the showcase are provided sensors 668, 668which control a refrigeration system 666 through a controller 665 whenthe electric field intensity becomes lower than a predetermined value.That is, in an electric field, cakes are not frozen at a temperature ofapproximately −3° C., and, accordingly, they can be stored at such atemperature. In this manner, in case that it is desired that they arestored at a minus temperature, they are frozen when the electric fieldstrength becomes small. Therefore, at this time, the sensors 668 detectits decrease to operate the refrigeration system 666 so as to raise thetemperature of the interior of the showcase to a plus range oftemperature. For example, in this case, the rotational number of acompressor in the refrigeration system is decreased or an expansionvalve is operated. The cakes are not frozen instantly when an electricfield is broken because of residual effect. If the eletrodes 663, 663 oneach shelf are connected in series to a high voltage generating device667, the sensor 668 may be provided on one of the shelves.

[0253]FIG. 89 shows a large warehouse which has an outer wall 620 whosepart forms a door 621. The floor of the warehouse is made of insulatingmember, and a conductive electrode plate 622 is buried in the floor. Theelectrode plate 622 is formed uprightly in the side wall of thewarehouse. The side wall 623 of the warehouse is also made of aninsulating member and vegetables such as potatoes and onions areaccommodated in the warehouse. Insulated (bare) electric wires 625 aredisposed in the warehouse to form an electrostatic field in the air ofthe warehouse. A bar-like or plate-like electrode 626 which is bare orcovered with an insulating coating is inserted into the vegetables 624.The electrode 626, insulated (bare) electric wire 625 and the electrodeplate 622 are connected to high voltage generating devices 628, 629,respectively, to impress a high voltage on the respective electrodes622, 625, 626. It is not necessary that all these electrodes areprovided, and either one may be provided. The door 621 has a safetyswitch 630 which stops the impression of a voltage thereon from highvoltage generating device 628, 629 when a forklift goes into thewarehouse with the door being opened. In order to form an electrostaticfield to objects such as potatoes and oranges, accommodated in a largecase, as shown in FIG. 90, an electrode 642 which is bare or coveredwith insulating coating is inserted into the objects 641, to be treated,contacted with each other in an insulating box 643, and the electrode isconnected to a high voltage generating device 640. With respect to amethod of impressing voltage on large pieces of meat such as beef andpork, as shown in FIG. 91, the large pieces of meat are suspended from aceiling 651, and a needle 654 as shown in FIG. 92 for each piece 652 isconnected to a high voltage generating device 653. In case that eachpiece contacts with each other, and one of them is stuck with the needle654, all pieces can be charged with electrocity because the pieceincludes water to facilitate the flow of an electric current.

[0254]FIG. 93 shows a prefab refrigerator which has a diabetic wall 660whose inner surface is, as occation demands, covered with an insulatingplate 668 such as vinylchloride plate. A movable rack 662 is disposed inthe refrigerator, and is insulated from the floor with insulating legs.The rack 662 has shelves 663, - - - 663 on which the above insulatedelectrodes 664 - - - 664 are put on the shelves 663, and an object to betreated is put on each insulated electrode 664. As occasion demands, anelectrode may be eliminated from one shelf so that a voltage of theelectrode on the shelf is induced on the other metal shelf. In order toform an electric field in the whole portion of the refrigerator, anelectrode 666 may be suspended from the ceiling as occasion demands.Each electrode 664 is connected to a high voltage generating device 661which is turned on or off in response to the operation of a proximityswitch (limit switch) and a light sensor 669 a. That is, when the door669 is opened, the high voltage generating device 661 is turned off, andwhen the door is closed, the high voltage generating device 661 isturned on. A known sensor 668 is provided above at least one electrode664 on the shelf to measure electric line of force thereof, and when themeasured value becomes a value less than a predetermined value (when theelectric field is broken), the refrigeration system is operated to raisea temperature in the refrigerator to a temperature more than 0° C., sothat the objects to be treated are not frozen.

[0255] With respect to a rack accommodated in a large refrigeratorincluding a prefab refrigerator, a rack 670 shown in FIG. 94 hassupports 671, 671 - - - 671 made of metal pipes which hold a metal shelf672. Each support 671 has, at its lower end, a caster 673 made ofinsulating body, which supports the rack from the floor in therefrigerator in an insulating state. The back face and both side facesare covered with an insulating plate (body) 674 such as vinylchloride,ABS resin and the like in such a manner that an electric current doesnot flow when the object to be treated contacts a conductive thinglocated around the rack. The insulating body 674 is not necessary incase that the inner wall of the refrigerator is covered with aninsulating plate and the rack is separated enough from the inner wall ofthe refrigerator. The shelf 672 may be detachably disposed on thesupports 671 in a sliding manner, and may be disposed so that itsvertical position can be adjusted with respect to the supports 671.

[0256]FIGS. 95 and 96 relate to an electrostatic field freshness-keepingsystem in distribution process of food, and FIG. 95 shows a fish,vegetable or fruit box 690. At the bottom of the fish box 690 isslidably provided a portable electrode 700 which has a machine portion701 provided with a battery-type transformer, and an electrode plate 702covered with an insulating coating 703 is connected to a high voltagegenerating device. The machine portion 701 comprises a batteryaccommodating portion 704 and a transformer accommodating portion 705.As a battery, a solar cell can be used, and the electrode 700 isinserted into an opening of the side face of the fish box through anopening 691. Fishes may be freshness-kept in a manner that the electrode700 is put directly on the fish box 690 on which fishes are locateddirectly. FIG. 97 shows a state in which fruits are put into a cardboardbox 710, on the bottom of which the electrode 700 is located. Theelectrode 700 must be provided per each box when a box for accommodatingfood is delivered by itself. That is, as shown in FIG. 98, when boxes722 are delivered in a refrigeration container, the boxes 722 which areformed conductive are piled up on a pallet 720, and these boxes 722 areput on an electrode 723 located on the pallet 720. In the pallet isprovided a high voltage generating device 724 of charging type by whicha high voltage is impressed on the electrode 723 to form anelectrostatic field in the whole portion of a box through thecircumferential wall of each box 722. It is preferable that the innerwall 725 of the container 721 is covered with an insulating plate suchas vinylchloride. In order to form an electrostatic field in the wholeportion of the container, an electrode 726 may be buried in the wall ofthe container so that a high voltage is impressed on the electrode 726.

[0257] In case that a pallet is not used in a refrigeration containersuch as a truck, as shown in FIG. 99, an electrode plate 740 is providedon the floor of a refrigerator or a container in an insulating state,and cardboard boxes 730 are mounted on the electrode 740. At this time,the electrode 700 in FIG. 97 is not necessary. In case that only adirect current power source 731 can be obtained in a truck and the like,a high voltage generating device 733 is operated through an alternatingelectric current transducer 732. Also in this case, the inner wall 734of the container is preferably made of an insulating body.

[0258]FIG. 100 shows a state in a large refrigerator such as arefrigeration warehouse. In general, fruits such as apples and a kind ofvegetables are stored in a refrigeration warehouse in a state that theyare accommodated in cardboard boxes. Cardboard boxes D put on pallets683, - - - 683 are piled up on, e.g., shelves 682, 682 - - - 682 ofsupport frames 680.

[0259] Each support frame 680 has vertical supports 681, - - - 681,which hold the shelf 682, and insulating casters 687 - - - 687 areprovided at the ends of the supports 681. The support frames 680 aredisposed in raw in the refrigeration warehouse, and control boxes 685are provided at an intermediate position of the floor between thedisposition of the support frames 680. Voltage of 100V is supplied to ahigh voltage generating device 684 from a control box 685. The controlboxes are buried in the floor so as not to obstruct the movement of aforklift. The control box may be suspended at a predetermined distancefrom the ceiling.

[0260] Each pallet 683 is, as shown in FIGS. 101 and 102, made ofplastic, and a bare electric wire 700 is buried in the pallet 683 so asto be connected to a high voltage generating device provided in thepallet. This high voltage generating device 684 is a charging-type one,and can be charged by connection of an electric power source of 100Vthrough a consent 701 when the objects to be treated are piled in thewarehouse. An electrostatic field of direct electric current by DCvoltage is formed when the objects are delivered. The fork 692 of aforklift is inserted into the pallet. The pallet 683 is made of plastic,and an iron plate 691 as an electrode may be put on the pallet. Theobjects to be treated are accommodated in a cardboard box D as anaccommodating body (box) which is mounted on the pallet 683. Apart ofthe wall of the cardboard box is formed conductive, and if eachcardboard box is formed conductive, an electric field can be formed inall cardboards boxes. That is, if the cardboard boxes piled contactedwith each other (even if they do not contact each other, an electricfield is induced when the conductive portions come close to each other),an electric field is generated in all cardboard boxes. The objects canfunction as an electrode, and an electric field is generated through theobjects. There are various ways for making conductive the wall of acardboard box, and, for example, a conductive sheet 711 maybe adhered onthe outer wall 710 of the cardboardbox. In addition, a conductive sheetmay be buried into the wall 710 of the cardboard box, and metal powdersmay be buried into the wall of the cardboard box. As shown in FIG. 104,conductive powder may be mixed with paste 716 for adhesion of aconnecting paper 715 for connecting the outer wall with the inner wall,and letters on the outer wall 710 may be written with conductive ink.

[0261] As shown in FIG. 105, e.g., an accommodating plate 720, forholding eggs, which is provided in a cardboard box may be formedconductive. That is, an accommodating plate accommodated in a large boxmay be formed conductive.

[0262]FIG. 106 shows a germinating apparatus 730 in which malt, radishand horseradish for water cultivation are cultivated. That is, thegerminating apparatus 730 has a vessel 731 in which water includingmaterial 734 is provided on which seeds are put. Water is supplied tothe water including material 734 through a tube 737, and the suppliedwater is charged with electron by connecting the vessel 731 to a highvoltage generating device 738 to make electron-charged water. Vegetablescultivated with the electron-charged water grow more quickly and can befreshness-kept because water in the vegetables is changed to waterdifferent from normal water. Especially, if malt, radish and the likefor water cultivation are put in a cardboard box, refrigerator and opencase for a supermarket in an electrostatic field, the freshness can beremarkably well kept. In FIG. 106, the electron-charged water is used aswater for water cultivation, and, however, it is desirable that anelectrode 739 connected to a high voltage generating device 738 isdisposed over the plants to be cultivated to form an electrostaticatmosphere in a space.

[0263]FIG. 107 shows a state of cultivation of plants. When plants arecultivated in an electrostatic field, they grow well, and noxiousinsects can be eliminated upon growing. That is, a plant 740 is coveredwith vinyl 741 to form a closed space in which a conductive wire 742 isdisposed, and conductive wire is connected to a high voltage generatingdevice 743. Plants grow remarkably well in such an electrostaticatmosphere.

[0264] As shown in FIG. 108, plants may be so cultivated that a metalnet 750 covered with vinyl is disposed over a seedbed for rice or aplace where other vegetables are planted in an insulated manner fromearth, and the metal net 750 is connected to a high voltage generatingdevice 751. It is found that plants grow well even if the same plantsare cultivated in the same place. The metal net 750 is supported by asupport 752, and an insulating body is provided at an intermediateportion of the support 752 to support the metal net in an insulatingmanner to earth.

[0265]FIGS. 109 and 110 show a cultivating cylinder 760 for plants,which is made of, e.g., transparent insulating member such as plastic,and whose bottom is inserted into the earth in a state of accommodatinga plant 761. A conductive body 762 is provided on the inner or outercircumferential surface in the shape of a band, and a high voltage isimpressed directly or indirectly on the conductive body 762. As shown inFIG. 110, a metal net 770 may be provided at the upper portion of thecultivating cylinder so that a high voltage is impressed on the metalnet 770. If a seedling is cultivated in an electric field in thismanner, noxious insects can be eliminated to promote its growing.

[0266]FIG. 111 shows a method of thawing in which frozen food is put inthe water stored in an insulated water tank 780. On the contrary, anelectrode 782 is put into the water, and is connected to a high voltagegenerating device 783.

[0267] In general, since frozen food does not melt at a temperatureunder −5° C. even in an electrostatic field, it is important that thetemperature of frozen food is adjusted in water or air so as to raiseits temperature quickly to 5° C. and then thawing is started in anelectrostatic field.

[0268] In general, thawing of fishes and shellfishes must be done for along time with those being dipped in water. However, if the thawing isdone in an electrostatic field, it needs only a short time. FIG. 113shows a thawing tank 790 which is made of concrete in which a metal wire791 is buried, the metal wire is connected to a high voltage generatingdevice 792. If the whole part of the thawing tank 790 is used as aninsulating body, and the water therein is exposed to an electrostaticatmosphere, fishes and shellfishes. 793 dipped in the water can bethawed for a short time. A bar-like insulating electrode 0.794 may bedipped without forming the whole portion of the thawing tank as aninsulated electrode body.

[0269]FIG. 114 shows a so-called electric field bath in which water isstored in an insulating tank 800, and an electrode 802 connected to ahigh voltage generating device 803 is inserted in the water 101. Theelectrode 802 may be a bare metal wire, and, however, it is preferablethat the electrode 802 is covered with an insulating coating because itis no good that the metal wire contacts directly the body of a humanbeing and other animals. In this case, as water is a good conductivebody, the water itself can not be charged with electrocity withoutstopping the flow of electrons.

[0270] Next, the adaptation of this invention for medical treatment willnow be explained.

[0271] In FIG. 115, a numeral number 810 shows a refrigerator whoseinner wall is made of a metal plate (not shown) which is covered with aninsulating coating, and this metal plate is connected to a high voltagegenerating device 813.

[0272] Blood accommodated in a vessel 814 is coolly stored in anrefrigerator 810. In general, blood of human being is stored atapproximately +4° C. in a constant temperature atmosphere. However, if avoltage of 50V-5 kV is impressed on the inner wall 812 thereof, anelectrostatic atmosphere is formed in the refrigerator 810 to charge theblood in the vessel 814 with electrocity, and it can be stored for alonger time than a conventional time without deteriorating the gradientof the blood. This blood is not frozen at a temperature of −4° C.-−5°C., and, therefore, it can be stored for a longer time at approximately−3° C. Further, blood is also frozen and stored through a quick freezingmethod, and, in this case, if blood is frozen in an electrostatic field,crystals of ice become small to enable the freezing of blood withoutbreakage of cell. When fish, meat and the like as well as blood arefrozen in a state of the impression of a voltage of 500V-2000V, crystalsof ice in the cell become small to enable the freezing without thebreakage of cell. Further, the blood can be thawed at a minustemperature of (approximately −3° C.), if thawing can be done withoutbreakage of cell, and it can be stored at a minus temperature for a longtime, maintaining a state of thawing of blood.

[0273] In general, in addition to blood transfusion, when internalorgans of a human being, such as a heart, lever, kidney or horny coat ofan eye are transplanted, if the refrigerator 810 is used as a gooddelivery box with an electric cell-type high voltage generating device813 (a battery charging type device can be used), the freshness of themcan be held, without freezing them, at a minus temperature for a longtime.

[0274] Bone marrow can be coolly stored, in the same manner, and,especially, spermatozoons and ovums are stored in a frozen state. Whenthe spermatozoons and ovums are thawed, there is no breakage of cell toenable an effective storing. A constant temperature control system 815is arranged therein because it is necessary to perform correctly thecontrol of temperature in a refrigerator for storing blood, and a partof the body of human being.

[0275] The inner wall 812 of the refrigerator 810 functions as anelectrode. However, instead, an electrode plate may be simply set on thefloor of a refrigerator to put a blood vessel thereon. Medicines andcosmetics for domestic use may be stored in this refrigerator to storethem for a long time.

[0276]FIG. 116 shows an electrostatic field house 80 whose floor or wallhas electrodes 821, 822, 823 therein, which are connected to a highvoltage generating device 824. On the contrary, at a predeterminedposition of a water pipe 821 is provided an impression portion 829 foran electrostatic field, the both ends of which are electricallyinsulated by insulating portions 826, 826, and the impression portion829 is connected to a high voltage generating device 824. If anelectrostatic field is formed in the house in this manner, ticks andfleas can be repulsed. Further, since an induction atmosphere can beformed in the house, a healthy environment can be obtained. The watercoming out of a cock 828 is a good electron-charged water which has beentreated in an electrostatic field during passing through the impressionportion 829.

[0277]FIG. 117 shows a raw flower storage apparatus M which has a casing830 in which shelves 831 are provided in an insulating state, and a highvoltage is impressed on the shelves 831 by a high voltage generatingdevice 833, and raw flowers 832 such as cut flowers are arranged on theshelves 831. A spray tube 836 is provided over the shelves 831, andwater fed from a water tank 825 by a water pump 834 is sprayed throughthe spray tube. If water in the water tank 825 is treated so as to beelectron-charged water, the freshness of the raw flowers can be keptbetter.

[0278] The electrostatic field functions to obtain a good dissolusionfor metal. As shown in FIG. 118, an electrode 842 provided on thecircumferential surface of a dissolving furnace 840 to form anelectrostatic atmosphere in the dissolving furnace 840 in which anelectric dissolution is performed by an electrode 841 (other dissolvingmethods can be adopted), so that a good dissolution for metal andmanufacturing of alloy become possible because oxidation is preventedduring reaction.

[0279] Further, as shown in FIG. 119, if an electrostatic field isformed in an internal-combustion engine 850 by a high voltage generatingdevice 851, combustion efficiency is increased and poisonous gas in agas discharged from a discharging tube 852 is decreased.

[0280] The electrostatic field treatment apparatus has a reductingfunction in this manner. Therefore, if a high voltage generating device871 is, as shown in FIG. 121, connected to a discharging system such asa muffler of an automobile to form an electrostatic atmosphere therein,a poisonous oxidation gas such as NO_(x) or CO₂ is decreased to protectan environmental pollution.

[0281]FIG. 120 is a view showing an electronic oven in which anelectrostatic field treatment apparatus is arranged. The inner wall 861formed of a conductive body such as graphite as non-metal material to bean electrode to which a high voltage generating device 865 is connected.A turntable 863 is provided at the lower portion of the electronic oven860, and an object 864 to be treated is put on the turntable 863. If amicrowave treatment is done in an electrostatic field in this manner, anobject 864 to be treated is cooked evenly.

[0282]FIG. 122 shows a pine weevil eliminating device 880 which has anelectrode 882 attached to a pipe tree 881, a voltage of 50-10 kV isimpressed on the electrode 882 from a high voltage generating device 883for a few minutes. Thereby, a pine weevil is eliminated.

[0283]FIG. 123 shows an electron-charged water supply apparatus 890which has a water tank supported on a table 893 through an insulatingplate and provided with a cock 894. The water tank has, at its backface, an electrode holding portion 898 in which an electrode 898 made ofmetal is accommodated, and the electrode 898 is connected to a highvoltage generating device 899 to make electron-charged water by chargingwater to be ionized in the water tank 891. The electrode 898 chargeswater in the water tank 891 through a circumferential wall thereof.However, the electrode 898 may be directly inserted into the water tank891 supported in an insulating state. A cup 895 is put under the cock894 provided on the front face of the water tank to be supported on atable 896. A water supply tube 900 is directed into the water tank 891to supply water thereinto. The electron-charged water ionized in thismanner becomes alkaline to increase slightly a value of PH and issuitable for water for drink.

[0284]FIG. 124 shows a fish farm 910 which has a pond formed so that aninsulating member 911 such as FRP is disposed in the earth, and fishessuch as trouts are bred. Charcoals 913 are spread out on the bottom ofthe pond into which an electrode 914 is inserted, and the electrode 914is connected to a high voltage generating device 915. The water in thepond is circulated by a water circulation apparatus. New water issupplied to the pond through a tube 921, pump 916 and a pipe 917. Waterin the pond is once stored in a first water storage tank 919, and thenis sent to a second water storage tank 920 by opening a valve V, andfurther is discharged by opening another valve V. That is, if dischargedwater flows to the earth continuously, water in the pond is not chargedwith electrocity, and therefore, water storage tanks should be providedin two steps because the discharged water must be electricallyinsulated.

[0285]FIG. 125 shows a water tank for appreciation in a Japaneserestaurant. The water tank is insulated by an insulating plate 930, andan electrode plate 931 is attached to the side face thereof. Thereby,water in the water tank is indirectly charged with electrocity. If waterin the water tank is charged with electrocity, a fungus is not attachedto fish, and fish grows more quickly, and, further, attachment of mossbecomes less. If charcoals are spread on the bottom of the water tank,the effect of electric charge is increased by function of far ultraredrays. This apparatus makes possible hatching of eggs of fish, and therate of hatching is remarkably increased.

[0286]FIG. 126 shows a maturing apparatus 940 for wine and sake. It isfound that the level of maturing of whisky and Japanese sake isremarkably increased in an electrostatic field. Namely, an insulatedelectrode 942 is put on a table 941, and the electrode is connected to ahigh voltage generating device 945. The maturing apparatus can be alsoadapted for making pickles. It is found that if pickles are treated inan electrostatic field, a good level of maturing is maintained for apredetermined time after the level of maturing of pickles reaches a goodvalue. That is, if pickles such as egg plants and cucumbers are made inan electrostatic field, a period of time from a time when they have beenmatured to a time when they have been soured is extended, whereby theperiod of time of good taste is extended.

[0287]FIG. 128 shows an electrostatic field water bed 960 and anelectrostatic pillow 955. The bag 961 of the water bed 960 includeswater 962 therein in which an electrode 963 (covered with insulatingcoating or without coating) is accommodated, and the electrode 963 isconnected to a high voltage generating device 964. An outer wrappingmember has the bag 961 therein and is made of cloth to be insulated, sothat a voltage is impressed on a man who lies (stays in air as aninsulating body) on the outer wrapping member.

[0288] A bag 957 has water therein on which a voltage from a highvoltage generating device 964 is impressed, and the bag 957 is coveredwith an outer covering member 958 to form an electrostatic field pillow.Instead of a water bed and a water pillow, conductive half-liquid bodyor solid body (fine powder body) may be used. In addition, it can bethought that swelling substance (substance included in a diaper) is putin a flexible and insulating bag such as plastic, and water is poured inthe bag at an actual spot to form a predetermined shape to make variouselectrodes.

[0289]FIG. 129 shows a rice storage apparatus in which an accommodatingcylinder 970 is provided to accommodate rice therein. The casing of theapparatus is earthed, and the accommodating cylinder itself is formed asan electrode which is so formed that a copper wire is buried in aninsulating body, and the copper wire is connected to a high voltagegenerating device 974. There are various ways for forming theaccommodating cylinder as an electrode. A conductive sheet may beadhered on the inner wall of the accommodating cylinder 970, and aplate-like conductive plate may be buried in an insulating member. Ifthe rice accommodating cylinder 970 is formed as an electrode toaccommodate rice therein, the taste of rice becomes well and thefreshness of rice is maintained.

[0290]FIG. 130 shows a rice cooker 980 put on a heating device 981, andcooked rice is accommodated in the main body of the rice cooker. Themain body thereof is closed with a cover plate 983, at the center ofwhich a bar-like insulating electrode 984 is supported in a statewherein the lower end is inserted in the cooked rice in the main body982 thereof. It is found that if rice is cooked in an electrostaticfield, it can be cooked well. A similar structure may be adapted for apressure cooker for cooking meat or chicken in addition to rice.

[0291]FIG. 131 shows a case in which an electrostatic field is formed ina large cooker. However, this can be adapted for domestic use. That is,a cylinder-like case (wall of the cooker) 990 has, therein, a plate-likeinsulated electrode 992 in a circular manner and accommodates a vessel993 detachably therein in which rice is put. The case 991 and vessel 993are closed with a cover member 995 by which a bar-like insulatingelectrode 996 is supported so that the lower end of the electrode 996 isinserted in the rice. It is not necessary that both of insulatingelectrode plate 992 and bar-like electrode 996 at the same time.

[0292]FIG. 132 shows a case of an electrostatic medical treatment inwhich a human body is located in an electrostatic field. An insulatedelectrode plate 1001 is put on a table 1000 for medical treatment, onwhich a mattress 1002 is located to lay a man 1003 thereon. Theinsulated electrode plate 1001 is connected to a high voltage generatingdevice 1004. If a man is laid in an electrostatic field, medicaltreatment is possible. In addition, if a dead body of a human being islaid on an insulated electrode plate 1001 in a dead body treatmentapparatus, the rotting speed of a dead body becomes slow. In this case,the dead body may be laid directly on the electrode plate without themattress.

[0293]FIG. 133 shows a so-called electrostatic pan 1010 which has aninsulating body 1011 such as ceramic in which a metal wire 1012 isburried, and the metal wire 1021 is connected to a high voltagegenerating device 1014 through a connecting portion 1013 so that thewhole portion of the pan 1010 forms an insulated electrode. The pan 1010is put on a gas table 1015, and a fire protection fin 1017 is formed atthe lower circumferential surface of the pan. Various cookings arepossible in an electrostatic field. It is found that if meat, fish andvegetable are cooked in an electrostatic field, the taste of thembecomes good. The metal wire 1021 may be made of a nicrome wire to useit as a heater and an electrode. Instead of the metal wire 1021, apan-like metal plate 1018 may be used as shown in FIG. 134.

[0294] Next, a concrete electric circuit for a high voltage generatingdevice used for the above various apparatuses.

[0295] In FIG. 135, a numeral number 1020 is a plug 1020 which isconnected to a domestic power source of 100V. The plug 1020 is connectedto a power switch 102, and a LED 1022 lights when the power switch 1021is turned on. The switch 1021 is connected to a transformer 1032 foroutputting 12V through a connecting terminal 1023, and electric currentfrom the transformer 1032 is rectified to be direct electric current soas to be inputted into a transistor 1024 (DC power source). On thecontrary, the switch 1021 is connected to a contact “a” of a relay 102D,and the contact “a” normally contact a contact “b” to be connected to achange-over switch 1026 through the terminal 1023. A switch 1026 forswitching selectably the secondary side output voltage of a transformer1027, and an electrode 1028 is disposed on the end portion of the secondside thereof via a resistance 1029 which restricts electric currentflowing to the electrode. For example, the resistance is selected sothat only electric current less than 2 mA flows into the electrode 1028for safety of a human body.

[0296] A contact “d” normally contacts a contact “e”, and a contact “f”does not contact the contact “e”, and the red LED 1030 a of an alarmdevice 1030 is off, and a blue LED 1030 b and a power switch 1022 areon. Further, at the center portion of the drawing are provided twooperational amplifiers 1031, 1032, between which a zener diode 1023 isdisposed to operate a transistor 1034 and the relay 1025 when abnormalelectric current flows in the circuit. Thereby, the contact “a” isseparated from the contact “b” and the contact “e” contacts the contact“f”. Therefore, at this time, the supply of electric current to thetransformer 1027 is stopped and the operational amplifier 1031 operatesso that the blue LED 1030 b of the alarm device 1030 becomes off and thered LED 1030 a becomes on.

[0297] The end of the secondary side of the transformer 1027 isconnected to the electrode plate 1028 via the resistance, and the otherend thereof is grounded through a resistance. Therefore, it is safebecause electric current more than a predetermined value does not flowin the circuit. Since the other end of the secondary side of thetransformer 1027 is earthed, a desired voltage can be impressed on theelectrode. In the case of the use of such a high voltage generatingdevice, if the voltage impressed on an electrode of a fryer isdetermined at 500-700V, the casing itself of the fryer is notnecessarily earthed, and only the earth for the high voltage generatingdevice is necessary. In case that an electric capacity for the whole ofthe fryer is large, the fryer itself can be used as an earth. In thecase of the use of a domestic refrigerator, if the refrigerator has anenough electric capacity, the refrigerator itself is not necessarilygrounded, and the earth for a high voltage generating device may beconnected to the case of the refrigerator. If the refrigerator does nothave an enough electric capacity for earth, a metal body may be providedon the case of the refrigerator if necessary.

[0298] Next, an electric circuit for a portable electrode will now beexplained.

[0299] In FIG. 136, the electric circuit comprises a voltage converter1040 for converting a voltage inputted by a battery into a high voltage,a switching circuit 1041 for making an alternating voltage to changeover the high voltage increased by the convertor 1040, and a voltageadjusting circuit 1042 for generating a voltage in response to afrequency. The voltage convertor 1040 has a transformer 1043 whoseprimary side is grounded via a transistor 1044 performing a switchingoperation. The flow of electric current is controlled by diodes 1045,1046, 1047, 1048, coils 1049, 1050 and condensers 1051, 1052 on thesecondary side of the transformer 1043 so that plus voltage and minusvoltage with the same value are changed over to make an alternatingvoltage. On the contrary, a voltage on the secondary side is comparedwith a reference voltage 1054 by a comparator 1053. When its differenceexceeds a predetermined value, a photo-isolator operates to drive apulse width control circuit 1056 at the time of detecting the lightning,so that the transistor 1044 performs a switch changing operation with apredetermined width of pulse. This system can be controlled so that thecondition of an object to be treated is detected by a sensor to send thedetected signal to a system controll portion 1061. In this case, asequence control is performed by a computer or timer.

[0300] If the contact of the transformer 1043 is moved upward, as shownin FIG. 137, an alternating voltage in which a negative voltage islarger than a positive voltage is generated. If the alternating voltageis impressed on the object to be treated, electrostatic field treatmentwith a strong reducing function is possible. Further, this pattern canbe adapted for an alternating power source, and, as shown in FIG. 138,negative ripple can be obtained.

[0301]FIG. 139 shows a circuit for a high voltage generating device 1070for a refrigerator or fryer. The high voltage generating device 1070 hasan alternating current power source 1071 which is turned on or off by aswitch 1072. The power source 1071 is connected to a transformer 1073,the one end of the secondary side of which is connected to an electrode1074, and the other end of which is grounded through a casing 1075. Asensor 1076 for measuring electric line of force is provided oppose tothe side face of the casing 1075 to turn off a switch 1072 through acontroller 1077 when the casing is accidentaly charged without thecasing being grounded. Thereby, an operator does not receive electricshock when he touches the casing with abnormality of earth.

[0302] As a safety device, ampere-meters 1078, 1078 can be provided onthe way between a transformer 1073 and an electrode 1074 or on anelectric wire for earth to turn off the switch 1072 when the decrease ofvalue of electric current is detected without a normal function ofearth.

[0303] When an impressed voltage on a fryer or refrigerator is low, thefryer itself and the refrigerator itself are not necessarily grounded.Further, in the case of a large electric capacity of the fryer and therefrigeration, the fryer itself and the refrigerator itself can be usedfor earth of a high voltage generating device.

[0304] When a system for forming an electrostatic field, of thisinvention, is assembled in a refrigerator, there is a case in which theinner wall of the refrigerator must be formed in an insulating state orthe electrode is covered with an insulating coating in order to preventelectric current from flowing when an object to be treated contacts theinner wall thereof. At this time, it is preferable to use an insulatingmaterial such as perhydropolysilazine which can be sprayed at a roomtemperature. Polysilazine is inorganic with a basic structure —SiH₂—NH—,and is synthesized so that ammonia is put in complex of zikurrosylaneand pyridine. Recently it is sold by TONEN (Japanese Company).

[0305] A high voltage of 100V-5000V can be impressed on an object to betreated in response to various objects. The above high voltagegenerating device is normally connected to a domestic power source witha frequency of 60 Hz or 50 Hz. In addition, a frequency may bechangeable by provision of a frequency changing apparatus in a circuit.It is found that the time of thawing is decreased with a frequency of120 Hz and 200 Hz.

[0306]FIG. 140 is a circuit of a high voltage generating device in whicha domestic power source is used as an earth, and a plug 1100 isconnected to an automatic judging circuit 1103 which automaticallyjudges the earthed side of the power source to connect it to the one end(earthed end) of the primary side and the end (earthed end) of thesecondary side of a transformer 1101, and the casing 1102 of arefrigerator or fryer. The provision of such a circuit 103 can eliminatean earth for the transformer 1101 and the casing 1102.

INDUSTRIAL APPLICABILITY

[0307] As mentioned above, electrostatic field treatment method andapparatus are suitable for freezing, thawing and freshness-keeping offood, prevention of oxidation of edible oil, and manufacturing ofelectron-charged water, etc.

1. A method of treating an object comprising the steps of: selecting anobject from the group consisting of blood of a human being, internalorgans thereof, bone marrow thereof, medicines and cosmetics; setting aconductive electrode in an insulated atmosphere to impress a voltage onthe conductive electrode to generate an electrostatic field around theconductive electrode; and placing the object to be treated in theelectrostatic field in an insulated state to perform storing, thawingand freezing.
 2. The method according to claim 1, wherein the object isset in a refrigerator and a voltage of 50V to 5 KV is impressed on theconductive electrode.
 3. The method according to claim 2, wherein therefrigerator is a delivery box with a battery for impressing a voltageon the conductive electrode.
 4. A method of treating a body of a humanbeing comprising the steps of: setting an insulated electrode plate on atable; and placing a body of a human being to be treated in anelectrostatic field generated by the insulated electrode plate toperform medical treatment or decrease of rotting speed of a dead body.5. An apparatus for treating an object the object comprising one ofblood of a human being, internal organs thereof, bone marrow thereof,medicines and cosmetics, the apparatus comprising: a conductiveelectrode disposed in an insulated atmosphere in a refrigerator; avoltage generating device for impressing a voltage on the conductiveelectrode for storing, thawing and freezing one of a human being,internal organs thereof, bone marrow thereof, medicines and cosmetics;and a constant temperature control system for keeping constant atemperature in the refrigerator.
 6. The apparatus according to claim 5,wherein the refrigerator is formed as a delivery box with a battery forimpressing a voltage on the conductive electrode.
 7. The apparatusaccording to claim 5, wherein the conductive electrode is formed by aninner wall of the refrigerator, and a voltage of 50V to 5 KV isimpressed on the conductive electrode.
 8. The apparatus according toclaim 5, wherein the voltage generating device generates an alternatingvoltage in which a negative voltage is larger than a positive voltage.9. An apparatus for treating a body of a human being comprising: aninsulated electrode plate set on a table for medical treatment of thehuman body or laying a dead body of a human being thereon; and a voltagegenerating device for impressing a voltage on the insulated electrodeplate to perform medical treatment or to decrease a rotting speed of thedead body.